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Theater Missile Defense

Missile Defense Systems Not Ready for Action, Pentagon Says

Wade Boese

A Pentagon office charged with evaluating proposed U.S. weapons systems reported to Congress in February that missile defense systems scheduled to be fielded in 2004 have not yet been proven to work.

As part of its annual assessment of weapons programs that are under development, the Pentagon’s office of Operational Test and Evaluation reviewed the status of the Missile Defense Agency’s ground-based midcourse defense system, sea-based system, Airborne Laser (ABL), and Theater High Altitude Area Defense (THAAD).

Thomas Christie, director of the operational test and evaluation office, wrote that the ground-based defense, which is designed to destroy warheads launched atop long-range ballistic missiles traveling through outer space, “has yet to demonstrate significant operational capability.”

Last December, President George W. Bush ordered that the initial fielding of this system begin in 2004 to “add to America’s security and serve as a starting point for improved and expanded [missile defense] capabilities later.” Bush also called for the deployment, by the end of 2005, of up to 20 missile interceptors based on ships to shoot down short- and medium-range ballistic missiles. (See ACT, January/February 2003.)

Christie identified three “major” testing limitations of the ground-based system. He pointed out that past testing has relied on a transmitter on the target for tracking purposes, has involved “unrealistic engagement[s] at relatively low altitudes,” and has been conducted with a rocket booster that accelerates more slowly than the one to be used in a final system.

Earlier Pentagon plans called for incorporating a more powerful booster in intercept testing in the first few months of 2001, but that is now scheduled to take place at the end of this year at the earliest. The new booster must still be selected from two competing versions this summer.

An independent review of the ground-based system released in November 1999 expressed concern that the system’s exoatmospheric kill vehicle (EKV)—a sensitive, light-weight device that is carried into space by the booster to seek out and collide with an incoming warhead—might not be able to withstand the shock loads of a more powerful booster. The review, conducted by the so-called Welch Panel, noted that the estimated shock loads of a new booster would be more than 10 times as great as those caused by the booster used in intercept testing.

In the eight intercept attempts to date, five of which resulted in the target’s destruction, the booster and EKV are launched toward the general area where, using data from the target’s transmitter, an intercept is projected to take place. The Missile Defense Agency (MDA), which oversees research and development of all missile defense programs, defends this practice by contending that there is no radar available in the testing area to perform the necessary tracking and that the EKV, after separating from its booster, does not receive any data from the transmitter.

MDA is seeking to develop a mobile, sea-based radar by late 2005. If MDA succeeds, the radar would presumably obviate use of the transmitter.

Test intercepts have all occurred approximately 220-240 kilometers above the Earth’s surface with the target and EKV coming together at a combined velocity of roughly 26,000 kilometers per hour. The similarity of all the tests reflects test-range constraints and prohibitions against creating space debris.

Christie noted that the testing limitations he cited “are not the result of [MDA’s] conscious decisions to minimize the test program, but result from an effort to gain early insight into system design at a reasonable pace and cost.”

In addition to addressing the testing limitations he had noted, Christie called on MDA to employ more realistic targets and countermeasures. He noted that balloon decoys used in past testing “were not intended to be representative of actual countermeasures, but to increase the number of objects to be tracked, without over-stressing the ground sensor or kill vehicle discrimination capabilities.”

Christie further recommended that MDA reduce the amount of information that the EKV is given about the target before the test. In testing to date, the EKV is provided details on the target and decoys so it can distinguish between them. Future tests “should reflect the operator’s imperfect knowledge of the characteristics of the threat,” Christie stated.

Status of Other MDA Programs

MDA’s sea-based system succeeded in all three of its intercept tests in 2002, but Christie observed that the “flight test engagement geometries, scenarios, and timelines were non-stressing.”

To make sea-based testing more challenging, Christie underscored the need to use a target that has a warhead which separates from its booster, a step MDA plans to take. The past three tests have involved a target that stays in one piece, making it easier to track and hit.

Although sea-based testing has been conducted from the actual ships tabbed for missile defense missions in the future, the report cautioned that the system could only be deployed “in an emergency with limited expectation of success.”

The ABL and THAAD programs, both of which are designed to counter short- and medium-range ballistic missiles, are even further behind in development.

ABL is to be tested for the first time against a ballistic missile target at the end of 2004, while THAAD’s next intercept test is set for the last months of 2005. THAAD tallied two hits and six failures in intercept testing between 1995 and 1999 before being put under redesign.

Neither ABL nor THAAD is advanced enough to be deployed even in an emergency. Christie noted that there is “no ABL emergency capability apart from some passive detection capabilities” and THAAD “has no operational capability because there is no deployable hardware.”

A Pentagon office charged with evaluating proposed U.S. weapons systems reported to Congress in February that missile defense systems scheduled to be fielded in 2004 have not yet been proven to work.

U.S. Missile Defense Programs at a Glance

For the past five decades, the United States has debated, researched, and worked on the development of defenses to protect U.S. territory against long-range ballistic missile attack. Yet, today, the United States remains far from being able to deploy effective and reliable strategic missile defenses.

The Bush administration inherited seven U.S. missile defense programs and two key satellite programs from the Clinton administration, but it has not been able to accelerate their development despite making missile defense a top priority and budgeting billions of additional dollars for the programs. In fact, most of the programs have experienced additional delays, and one sea-based system has been canceled because of poor performance, spiraling costs, and schedule problems.

The Bush administration has reorganized missile defense programs, placing the separate programs under one big tent. And, whereas previous U.S. administrations drew a distinction between theater defenses (those designed to hit short- and medium-range ballistic missiles) and strategic defenses (those intended to intercept long-range missiles/ICBMs), the Bush administration is pursuing what it calls a general research and development program. Nevertheless, for the most part the Pentagon continues to work on each program individually, as it did during the Clinton administration, albeit with an eye toward sharing technology among the systems and expanding some theater programs to tackle a strategic mission.

Although the Bush administration singled out the 1972 Anti-Ballistic Missile (ABM) Treaty as the primary impediment to development of U.S. missile defense systems, the June 13 U.S. withdrawal from the accord is unlikely to hasten missile defense deployment. Lieutenant General Ronald Kadish, who is director of the Pentagon’s Missile Defense Agency, recently testified that two benefits of the U.S. treaty withdrawal would be the freedom to test whether a specific sea-based radar can be used to track a strategic ballistic missile target and to deploy strategic missile defenses when they are available. (The treaty bans Moscow and Washington from fielding nationwide strategic defenses but places no restrictions on theater missile defense systems.)

But two Pentagon reports have already concluded that the radar in question is not capable of supporting or performing a national missile defense role, and no strategic missile defense systems will be ready for deployment for at least several years. At this time, only one U.S. missile defense program—the national missile defense program initiated by the Clinton administration—is being tested against strategic ballistic missiles, and the only “deployment” plan is for five missile interceptors to be fielded in Alaska by 2004, ostensibly for testing purposes. This represents a scaling back of the Clinton plan that called for an initial deployment of 20 operational missile interceptors in Alaska by 2005.

The following chart provides a brief look at each of the Pentagon’s major missile defense programs. It contains information on what type of ballistic missile each defense would be intended to counter and at which stage of the enemy missile’s flight an attempted intercept would take place. (For a brief description of ballistic missiles, how they are classified, and their three stages of flight, see “Ballistic Missile Basics” below.) Also included are Pentagon estimates on when each defense may have an initial, rudimentary capability as well as when it may be fully operational. Information on the status of each program, including testing delays, is also detailed.

Ballistic Missile Basics

Ballistic missiles are classified by the maximum distance that they can travel, which is a function of how powerful the missile’s engines (rockets) are and the weight of the missile’s warhead. To add more distance to a missile’s range, rockets are stacked on top of each other in a configuration referred to as staging. There are four general classifications of ballistic missiles:

  • Short-range ballistic missiles, traveling less than 1,000 kilometers (approximately 620 miles)
  • Medium-range ballistic missiles, traveling between 1,000–3,000 kilometers (approximately 620-1,860 miles)
  • Intermediate-range ballistic missiles, traveling between 3,000–5,500 kilometers (approximately 1,860-3,410 miles)
  • Intercontinental ballistic missiles (ICBMs), traveling more than 5,500 kilometers

Short- and medium-range ballistic missiles are referred to as theater ballistic missiles, whereas ICBMs or long-range ballistic missiles are described as strategic ballistic missiles. The ABM Treaty prohibited the development of nationwide strategic defenses, but permitted development of theater missile defenses.

All ballistic missiles have three stages of flight:

  • The boost phase begins at launch and lasts until the rocket engines stop firing and pushing the missile away from Earth. Depending on the missile, this stage lasts between three and five minutes. During much of this time, the missile is traveling relatively slowly, although toward the end of this stage an ICBM can reach speeds of more than 24,000 kilometers per hour. The missile stays in one piece during this stage.
  • The midcourse phase begins after the rockets finish firing and the missile is on a ballistic course toward its target. This is the longest stage of a missile’s flight, lasting up to 20 minutes for ICBMs. During the early part of the midcourse stage, the missile is still ascending toward its apogee, while during the latter part it is descending toward Earth. It is during this stage that the missile’s warhead, as well as any decoys, separate from the delivery vehicle.
  • The terminal phase begins when the missile’s warhead re-enters the Earth’s atmosphere, and it continues until impact or detonation. This stage takes less than a minute for a strategic warhead, which can be traveling at speeds greater than 3,200 kilometers per hour


Ground-Based Midcourse Defense

(Referred to as National Missile Defense by the Clinton administration)

Program & Key Elements

  • The key element of the ground-based midcourse defense is a ground-based missile interceptor consisting of a powerful multistage booster and an exoatmospheric kill vehicle (EKV), which separates from the booster in space and seeks out its target through radar updates and use of its onboard visual and infrared sensors.
  • The EKV destroys its target by colliding with it. This process is referred to as hit-to-kill
Designed to Counter
  • The projected system’s goal is to intercept strategic ballistic missiles in their midcourse stage
  • To date, the system has four successful intercept attempts in six developmental tests.
  • The next intercept attempt is scheduled for August.
  • The development of the multistage booster for the EKV is more than 18 months behind schedule.
  • The proposed booster failed its second flight test on December 13, 2001, within 30 seconds of its launch.
  • A second U.S. company has been contracted to develop an alternative booster
  • The Pentagon is currently planning to deploy five test missile interceptors at Fort Greely in Alaska by September 2004.
  • Although not considered an actual deployment, the five interceptors could provide an “emergency capability” if needed, according to Pentagon officials.
  • Currently, there are no plans to use the missiles from Fort Greely in tests because of safety concerns.
  • Clinton’s missile defense plans called for deployment of 20 missile interceptors in Alaska by 2005.
  • The interceptors under the Clinton plan would have been supported by an X-band radar, which the Bush proposal does not currently include.
  • Instead, Bush’s plans call for the missile interceptors to be supported by an upgraded, though less capable, early-warning radar on Shemya Island at the western tip of the Aleutian Island chain.


Sea-Based Midcourse Defense
(Referred to as Navy Theater Wide by the Clinton administration)

Program & Key Elements

  • The key elements of the proposed sea-based defense are a ship-based missile (Standard Missile-3, or SM-3) and the Aegis combat system, an advanced system that can detect and track more than 100 targets simultaneously while directing a ship’s weapons to counter incoming air, surface, and submarine threats.
  • The SM-3 is a hit-to-kill missile comprised of a three-stage booster with a kill vehicle.
  • Two Pentagon reports have declared that the Aegis combat system, particularly its radar, is not capable of supporting a strategic missile defense mission.
  • The SM-3 is also considered too slow to intercept a strategic ballistic missile.
Designed to Counter
  • Initially, the sea-based midcourse defense is geared toward defending against short-, medium-, and interme- diate-range ballistic missiles during their midcourse stage with an emphasis on the ascent phase.
  • Eventually, the Pentagon wants the defense to be capable of countering strategic ballistic missiles, possi- bly in the boost phase.
  • A senior Pentagon official announced May 2 that the Pentagon would also explore whether the system can be adapted to counter short- and medium-range missiles in their terminal stage.
  • In a January 25 test, the system intercepted a target for the first time, but the flight paths of the two objects had been plotted in such a way that an intercept was expected. A second test in June, which was described as “identical” to the first, also succeeded.
  • The next test is tentatively scheduled for November.
  • Clinton administration plans called for five intercept attempts to be completed by September 2002, but the program will have completed two intercept tries at most by that time.
  • The Bush administration has stated it would like to have a sea-based system available by 2004 as part of a rudimentary, emergency capability against short- and medium-range ballistic missile threats.
  • The Pentagon is seeking to deploy four ships outfitted with a midcourse defense between 2006 and 2008.
  • Lieutenant General Ronald Kadish, who is director of the Pentagon’s Missile Defense Agency, estimated last July that testing the system against long-range ballistic missiles could begin in 2007 or 2008.

Airborne Laser (ABL)

Program & Key Elements

  • The key element of the proposed ABL system is a modified Boeing 747 plane equipped with a chemical oxygen-iodine laser.
  • The laser beam is produced by a chemical reaction
Designed to Counter
  • Although the Pentagon originally aimed to field the ABL against theater ballistic missiles, the Pentagon now contends the ABL may have an inherent capability against strategic ballistic missiles as well.
  • The expanded ABL objective is to shoot down all ranges of ballistic missiles in their boost phase.
  • Construction of the first test plane and its laser are underway.
  • First attempt to intercept a ballistic missile target is scheduled for the fall of 2004.
  • The Clinton administration planned for the first ABL intercept attempt to take place in 2003.
  • The Pentagon is seeking to have one ABL available by 2004 for use in emergencies.
  • The Pentagon aims to have two or three ABLs between 2006 and 2008.
  • The Pentagon’s ultimate goal is a fleet of seven aircraft by 2011.


Theater High Altitude Area Defense (THAAD)

Program & Key Elements

  • THAAD’s main components are a missile comprised of a single rocket booster with a separating kill-vehicle that seeks out its target with the help of a specifically designed THAAD radar.
  • The THAAD kill vehicle is hit-to-kill.
  • THAAD missiles are fired from a truck-mounted launcher.
Designed to Counter
  • THAAD’s mission is to intercept short- and medium-range ballistic missiles during their terminal stage.
  • The system had two successful intercept attempts in the summer of 1999 after experiencing six test failures between April 1995 and March 1999.
  • The THAAD missile is currently being redesigned.
  • THAAD flight tests are scheduled to resume in 2004.
  • The Pentagon initially aims to field the system in 2007 or 2008.


Patriot Advanced Capability-3 (PAC-3)

Program & Key Elements

  • PAC-3 consists of a one-piece, hit-to-kill missile interceptor fired from a mobile launching station, which can carry 16 PAC-3 missiles.
  • The missile is guided by an independent radar that sends its tracking data to the missile through a mobile engagement control station.
Designed to Counter
  • PAC-3 is designed to defend against short- and medium-range ballistic missiles in their terminal stage at lower altitudes than the THAAD system.
  • Operational intercept testing started in February 2002 with a test failure.
  • A March 21 operational test, the second, resulted in a PAC-3 hitting its target, though a second PAC-3 missile did not fire as called for in the test.
  • An April 25 operational test, the third, was initially reported as a success, but the Army later announced that the PAC-3 missile did not destroy the target. A second PAC-3 missile failed to launch.
  • In a fourth, and reportedly final, operational test in this testing series, a PAC-3 missile hit its target on May 30, but a second PAC-3 missile failed to fire as planned.
  • During earlier developmental testing, the system struck nine out of 10 targets.
  • The Pentagon declared on September 26, 2001, that a limited number of PAC-3 missiles were available for deployment.
  • The Army has a projected inventory of 2,200 PAC-3 missiles.
  • A decision on the pace of production for the PAC-3 missile is scheduled for September 2002.
  • The Pentagon’s fiscal year 2003 budget request calls for funding to procure 1,159 PAC-3 missiles.
  • A senior Pentagon official testified April 17, 2002, that “over 20” PAC-3 missiles are already in deployment status.


Navy Area Theater Ballistic Missile Defense (NATBMD)

Program & Key Elements

  • NATBMD was a ship-based system consisting of the Standard Missile-2 (SM-2) and Aegis combat system.
  • Unlike other U.S. missile defense programs the SM-2 was armed with a blast fragmentation warhead and was not a hit-to-kill system.
Designed to Counter
  • The system was intended to intercept short- and medium-range ballistic missiles in their terminal stage.
  • The Bush administration canceled the program on December 14, 2001, because of poor performance, projected cost overruns, and schedule delays.
  • A senior Pentagon official announced May 2, 2002, that the Pentagon would not pursue development of a new naval terminal system.
  • As an alternative to a new program, the Pentagon will study whether the sea-based midcourse defense can be modified so that it can also deal with theater missiles in their terminal stage.


Space-Based Laser (SBL)

Program & Key Elements

  • The proposed system’s main element would be a satellite armed with a hydrogen-fluoride chemical laser.
Designed to Counter
  • The SBL is being developed to counter all ranges of ballistic missiles in their boost phase.
  • Pentagon plans during the Clinton administration called for a first space test in 2012, but funding cuts have pushed back the initial test date indefinitely, although recent reports suggest the Pentagon is exploring ways to accelerate the program.
  • No official estimate exists on a possible deployment date.


Space-Based Infrared System-low (SBRIS-low)

Program & Key Elements

  • SBIRS-low is to be comprised of approximately 30 satellites in low-Earth orbit.
Designed to Counter
  • The SBIRS-low satellites are expected to support U.S. missile defense systems by providing tracking and discrimination data on warheads and decoys during their midcourse stage.
  • The first launch of a SBIRS-low satellite was to take place in fiscal year 2006, but the program is currently being restructured because of high costs and schedule delays.
  • A senior Pentagon official said May 2, 2002, that an initial launch of a SBIRS-low payload could occur in 2006 or 2007.
  • During the Clinton administration, Pentagon plans called for full deployment by fiscal year 2010.
  • No official estimate exists on a possible deployment date.


Space-Based Infrared System-high (SBIRS-high)

Program & Key Elements

  • SBIRS-high will be comprised of four satellites in geosynchronous Earth orbit and sensors on two host satellites in a highly elliptical orbit.
Designed to Counter
  • SBIRS-high’s primary objective is to provide early warning of global ballistic missile launches.
  • The first launch of a geosynchronous satellite was scheduled to occur in fiscal year 2005, but it is now scheduled for fiscal year 2007.
  • The first payload for the two satellites in a highly elliptical orbit is to be ready by 2003.
  • An Air Force spokesperson reported May 21 that current expectations are that the full SBIRS-high system will be operational “on or about 2011.”



PAC-3 Production to Continue Despite Program Shortcomings

July/August 2002

By Wade Boese

Despite failures in each of its last four intercept tests, production and deployment of the Patriot Advanced Capability-3 (PAC-3) missile defense system should continue, a senior Pentagon official said June 20.

Lieutenant General Ronald Kadish, who oversees U.S. missile defense programs, expressed disappointment that PAC-3 had fallen short of expectations in recent testing but recommended that U.S. deployment of the ground-based, tactical missile defense system not be halted. “We ought to proceed putting that weapons system in the field as soon as we possibly can,” the general stated in a public briefing.

Kadish urged continued deployment of PAC-3, which is designed to intercept short- and medium-range ballistic missiles, cruise missiles, and aircraft, because the United States has “no capability out there today that is the equivalent of the Patriot-3.”

The Army announced last year that it had PAC-3 missiles ready for deployment, and now more than 20 are stockpiled for use. Low-rate production of the system is ongoing, and a PAC-3 program official said, “We do not anticipate a break in production.”

Kadish stated that fixing the problems revealed by the recent testing, which he said were “not severe,” and continuing production and deployment could be done together. “The decision on Patriot is to work out the difficulties we found and improve the system over time and build as much as we can afford in the process,” Kadish said.

After missing only one of 10 targets in developmental testing, the PAC-3 system experienced problems in every operational test conducted between February and May. In operational testing, actual soldiers participate in testing the system under more realistic battlefield scenarios than those conducted by contractor personnel in developmental testing.

Three of the four operational tests involved simultaneously launching multiple Patriot missiles, both PAC-3 and the earlier PAC-2 versions, at multiple targets. The final test called for two PAC-3 missiles to be fired automatically in quick succession against a single target.

A PAC-3 interceptor missed its target in the first test, and in each of the last three tests a PAC-3 missile failed to launch as planned. In sum, PAC-3 missiles destroyed two of the five targets assigned them. One PAC-3 missile hit its target but did not destroy it.

Each test failure resulted from a different problem, according to the Pentagon, although analysis of the last failure is still underway. In one test, for example, the missile received an inaccurate cue from a ground-based computer, but in another, the PAC-3 missile launcher lost power during the firing sequence.

The PAC-3 program official downplayed the test failures, claiming none “indicate a systemic problem with the PAC-3 missile or with PAC-3 ground equipment.” For his part, Kadish acknowledged, “We got some bugs in the system we’ve got to work out,” but he expressed confidence that the problems will be fixed.

No future PAC-3 test is currently scheduled, although additional testing is expected.

Pentagon officials were scheduled to make a decision on whether to accelerate PAC-3 production this September from low-rate to full-rate production, but Kadish implied that would not happen, saying the Pentagon does not “necessarily know at this point what full-rate production ought to be.” Instead, Kadish said, “We intend to build at a low rate or a rate that we can afford at this point in time.”

The Army’s declared inventory objective is at least 2,200 PAC-3 missiles, but Kadish testified at an April 17 hearing of the Senate Appropriation Committee’s defense subcommittee that he thought that figure would be adjusted over time.

PAC-3 Production to Continue Despite Program Shortcomings

Rhetoric or Reality? Missile Defense Under Bush

Philip Coyle

Since it assumed office, the administration of President George W. Bush has made missile defense one of its top priorities, giving it prominence in policy, funding, and organization.

First, the administration outlined an ambitious set of goals that extend well beyond the Clinton administration’s missile defense aims. In early January 2002, Secretary of Defense Donald Rumsfeld described the administration’s top missile defense objectives this way: “First, to defend the U.S., deployed forces, allies, and friends. Second, to employ a Ballistic Missile Defense System (BMDS) that layers defenses to intercept missiles in all phases of their flight (i.e., boost, midcourse, and terminal) against all ranges of threats. Third, to enable the Services to field elements of the overall BMDS as soon as practicable.”

Then, in its nuclear posture review, the administration outlined the specific elements of a national missile defense that it wants to have ready between 2003 and 2008: an air-based laser to shoot down missiles of all ranges during their boost phase; a rudimentary ground-based midcourse system, a sea-based system with rudimentary midcourse capability against short- and medium-range threats; terminal defenses against long-range ICBMs capable of reaching the United States; and a system of satellites to track enemy missiles and distinguish re-entry vehicles from decoys.

Finally, to speed implementation, the administration has taken a number of tangible steps. It announced on December 13, 2001, that the United States would withdraw from the 1972 Anti-Ballistic Missile (ABM) Treaty, ostensibly because the treaty was restricting testing of mobile missile defenses against ICBMs. In its first defense budget, the administration requested a 57 percent increase in funding for missile defense—from $5.3 billion to $8.3 billion, of which it received $7.8 billion. Then, Rumsfeld reorganized the Ballistic Missile Defense Organization into the new Missile Defense Agency, cancelled the internal Pentagon documents that had established the program’s developmental goals, and changed the program’s goal from being able to field a complete system against specific targets to simply being able to field various missile defense capabilities as they become available.

All in all, a lot has happened in missile defense in the first year or so of the Bush administration. But have these actions brought the United States any closer to realizing its missile defense goals, especially deployment of a national missile defense? And what elements, if any, of a national missile defense capability might it be possible for the United States to deploy by 2008, as called for in the nuclear posture review?

Despite the Bush administration’s push for missile defense, the only system likely to be ready by 2008 is a ground-based theater missile defense intended to counter short-range targets—i.e., a system to defend troops in the field. Before Bush leaves office, the only system that could conceivably be ready to defend the United States itself is the ground-based midcourse system pursued by the Clinton administration. None of the other elements mentioned in the nuclear posture review as possible defenses against strategic ballistic missiles is likely to be available by 2008.

To understand why, let us examine each of the missile defense programs—starting with the short-range, theater missile defense systems and moving to the longer-range, strategic systems—to see what has happened since the Bush administration took office 16 months ago. The results suggest that the Bush administration should not base its foreign policy on the assumption that during its tenure it will be able to deploy defenses to protect the United States from strategic missiles.

Theater Missile Defenses

Each of the U.S. military services has been pursuing tactical missile defense programs designed to defend U.S. troops overseas. None of these programs was designed to defend the United States against ICBM attacks, and none has any current capability to do so. However, the administration hopes to be able to apply some of the technology from these service programs to a layered national defense capable of defending the U.S. homeland. (For an explanation of the various stages of development discussed below, see the box below.)


The Patriot Advanced Capability-3 (PAC-3) is a tactical system designed to defend overseas U.S. and allied troops in a relatively small area against short-range missile threats (such as Scuds), enemy aircraft, and cruise missiles. Developmentally, it is the most advanced U.S. missile defense system, and a small number have been made available for deployment although testing has not yet been completed.

PAC-3 flight testing began in 1997. From 1997 to 2002, 11 developmental flight tests were conducted, including four flight intercept tests with two or three targets being attempted at once. Most of these tests were successful, but in two of the tests one of the targets was not intercepted. In February, PAC-3 began initial operational testing, in which soldiers, not contractors, operate the system. Three operational tests have been conducted, all with multiple targets. In each, one of the targets has been missed or one of the interceptors has failed.

A year ago, PAC-3 was planned to begin full-rate production at the end of 2001. However, problems with system reliability and difficulties in flight intercept tests have delayed that schedule. This means that full-rate production likely will be delayed until more stressing “follow-on” operational tests can be conducted against targets flying in a wide range of altitudes and trajectories. In March, Lieutenant General Ronald Kadish, who heads U.S. missile defense programs, testified to Congress that the full-rate production decision would be made toward the end of 2002 (before operational testing has been completed), representing a delay of about a year since last year. The full system will be deployed once all operational testing has been completed, perhaps around 2005.

A future version of PAC-3 is being considered for terminal defense of the United States. However, PAC-3 was not designed to counter long-range threats, and no flight intercept tests have been conducted to demonstrate how it might be incorporated in a terminal defense layer. Further, the ground area that can be defended by PAC-3 is so small that it would take scores of systems to defend just the major U.S. cities. A version of PAC-3 that could be effective in a national missile defense is probably a decade away.


The Theater High Altitude Air Defense (THAAD) system is designed to shoot down short- and medium-range missiles in their terminal phase. THAAD would be used to protect forward-deployed troops overseas as well as nearby civilian populations and infrastructure. THAAD is to defend a larger area against longer-range threats than PAC-3, but it is not designed to protect the United States from ICBMs.

From 1995 to 1999, 11 developmental flight tests were performed, including eight in which an intercept was attempted. After the first six of those flight intercept tests failed, the program was threatened with cancellation. Finally, in 1999, THAAD had two successful flight intercept tests. The THAAD program has not attempted an intercept test since then, instead focusing on the difficult task of developing a new, more reliable, higher-performance missile than the one used in early flight tests.

A year ago, full-rate production was scheduled to begin in 2007 or 2008, but because there were no intercept tests in 2000 or 2001, that schedule has likely slipped two years or more. In fact, no flight intercept test is scheduled until 2004, and it is therefore unlikely that the first THAAD system will be deployed before 2010.

The Bush administration is considering THAAD for use in a layered national missile defense system. Conceptually, THAAD might be used in conjunction with PAC-3 as part of a terminal defense, or it could be deployed overseas to intercept enemy missiles in the boost phase. However, in its current configuration THAAD is incapable of performing these missions—even once it has met its Army requirements for theater missile defense—and therefore a role for THAAD in national missile defense is probably more than a decade away.

Navy Area Theater Ballistic Missile Defense

The Navy Area Theater Ballistic Missile Defense was the sea-based equivalent of PAC-3. The Navy Area system was being designed to defend forward-deployed Navy ships against relatively short-range threats. But in December 2001 the program was cancelled because its cost and schedule overruns exceeded the limits defined by law. (Ironically, the cancellation came just one day after President Bush announced that the United States would pull out of the ABM Treaty because its missile defense testing was advanced enough to be bumping up against the constraints of the treaty.)

The Navy still wants to be able to defend its ships against missile attack, and the program will most likely be restructured and reinstated once the Navy decides on a new approach. In the meantime, the Navy Area program is slipping with each day that passes. As with PAC-3, the Bush administration has considered extending the Navy Area system to play a role in the terminal segment of a layered national missile defense. However, at this point the program is too poorly defined to allow speculation about when it could accomplish such a demanding mission.

Navy Theater Wide

The Navy Theater Wide program was originally intended to defend an area larger than that to be covered by the Navy Area system—that is, aircraft carrier battle groups and nearby territory and civilian populations—against medium-range missiles during their midcourse phase. In this sense, Navy Theater Wide is the sea-based equivalent of THAAD.

In January, the Navy Theater Wide program conducted its first successful flight intercept test, but a dozen or more developmental flight tests will be required before it is ready for realistic operational testing. About a year ago, full-rate production was scheduled for spring 2007, meaning that the system could be deployed before the end of the decade.

But since then, the Pentagon has given new priority to a sea-based role in defending the U.S. homeland. Navy Theater Wide was not designed to shoot down ICBMs, but the Bush administration has restructured the program so that it aims to produce a sea-based midcourse segment and/or a sea-based boost-phase segment of national missile defense.

Either mission will require a new missile that is twice as fast as any existing version of the Standard Missile, which the system now uses; a new, more powerful Aegis radar system to track targets; a new launch structure to accommodate the new, larger missiles; and probably new ships. As a result, the Navy Theater Wide program requires a great deal of new development. It is unlikely that Navy Theater Wide will be ready for realistic operational testing until late in this decade, and it will not be ready for realistic operational demonstration in a layered national missile defense for several years after that.

Airborne Laser

The Airborne Laser (ABL) is a program to develop a high-power chemical laser that will fit inside a Boeing 747 aircraft. It is the most technically challenging of any of the theater missile defense programs, involving toxic materials, advanced optics, and the coordination of three additional lasers on-board for tracking, targeting, and beam correction. The first objective of the program is to be able to shoot down short-range enemy missiles. Later, it is hoped the ABL program will play a role in national missile defense by destroying strategic missiles in their boost phase.

The ABL has yet to be flight-tested. About a year ago, full-rate production of the ABL was scheduled for 2008. The plan was to build seven aircraft, each estimated to cost roughly $500 million. At that time, the first shoot-down of a tactical missile was scheduled for 2003. Recently, the ABL program office announced that the first shoot-down of a tactical missile had been delayed to late 2004 because of many problems with the basic technology of high-power chemical lasers—about a one-year slip since last year and about a three-year slip since 1998. Accordingly, full-rate production probably cannot be started before 2010, and the cost will likely exceed $1 billion per aircraft.

Assuming all this can be done, it is important to note that the ABL presents significant operational challenges. The ABL will need to fly relatively close to enemy territory in order to have enough power to shoot down enemy missiles, and during a time of crisis it will need to be near the target area continuously. A 747 loaded with high-power laser equipment will make a large and inviting target to the enemy and will require protection in the air and on the ground. Finally, relatively simple countermeasures such as reflective surfaces on enemy missiles could negate the ABL’s capabilities.

Deployment of an ABL that can shoot down short- and medium-range tactical targets is not likely before the end of the decade, and the Airborne Laser will not be able to play a role in national missile defense for many years after that.

National Missile Defense

The Bush administration hopes to build a layered national missile defense that consists of a ground-based midcourse system, expanded versions of the theater systems discussed above, and, potentially, space-based systems. The Bush administration does not use the phrase “national missile defense” because it was the name of the ground-based midcourse system pursued by the Clinton administration and because the Pentagon’s plans to defend the country are now more robust. But national missile defense is a useful shorthand for any system that is intended to defend the continental United States, Alaska, and Hawaii against strategic ballistic missiles, and it is in that sense that it is used here.

For all practical purposes, the only part of the Bush national missile defense that is “real” is the ground-based midcourse system. It is real in the sense that six flight intercept tests have been conducted so far, whereas versions of the THAAD or Navy Theater Wide systems that might be used to defend the United States have not been tested at all. Space-based systems are an even more distant prospect. For example, the Space-Based Laser, which would use a laser on a satellite to destroy missiles in their boost phase, was to be tested in 2012, but funding cuts have pushed the testing date back indefinitely. Deployment is so far in the future that it is beyond the horizon of the Pentagon’s long-range planning document, Joint Vision 2020.

As a result, despite the Bush adminis-tration’s attempts to distinguish its plans from its predecessor’s, Bush’s layered national missile defense is, in effect, nothing more than the Clinton system.
Since 1997, the ground-based midcourse program has conducted eight major flight tests, known as IFTs. The first two, named IFT-1A and IFT-2, were fly-by tests designed simply to collect target information. The next six tests, IFT-3 through IFT-8, were all flight intercept tests. IFT- 4 and IFT-5, conducted in January 2000 and July 2000 respectively, both failed to achieve an intercept, which became a principal reason why, on September 1, 2000, President Bill Clinton decided not to begin deployment of ground-based midcourse components, such as a new X-band radar on Shemya Island in Alaska.

Another year passed before the next flight intercept test, IFT-6, was conducted. The intercept was successful except that the real-time hit assessment performed by the ground-based X-band prototype radar on the Kwajalein Atoll in the Marshall Islands incorrectly reported the hit as a miss. IFT-7, conducted in early December 2001, was also successful. Until then, all of the flight intercept tests had had essentially the same target cluster: a re-entry vehicle, a single large balloon, and debris associated with stage separation and decoy deployment. Then, in IFT-8, conducted on March 15, 2002, two small balloons were added to the target cluster. This flight intercept test also was successful and marked an important milestone for the ground-based midcourse program.

However, despite these recent successes, there have been significant delays in the testing program. Several of the flight tests were simply repeats of earlier tests, and as a result IFT-8 did not accomplish the tasks set for it in the original schedule. In short, the testing program has slipped roughly two years—i.e., what was originally scheduled to take two years has taken four. This is not to say that the program has made no progress but rather that key program milestones have receded into the future.

The pace of successful testing will be one of the primary determinants of how quickly the United States can field a national missile defense. If the ground-based midcourse system has three or four successful flight intercept tests per year, as it has during the past year, it could be ready for operational testing in four or five years. If those operational tests also were successful, then whatever capability had been demonstrated in all those tests—which would probably not include the capability to deal with many types of decoys and countermeasures or the capability to cover much of the space through which an enemy missile could travel—could be deployed by the end of the decade or even by 2008.

However, the ground-based midcourse system has difficulties beyond the testing pace of its interceptor. The system requires a new, more powerful booster rocket than the surrogate currently being used in tests—a task that was thought to be relatively easy. That new booster was to be incorporated into the continuing series of flight intercept tests to make those tests more realistic and to be sure that the new booster’s higher acceleration did not adversely affect other components or systems on board.

But development of the new booster is about two years behind schedule. Indeed, on December 13, just hours after President Bush announced U.S. plans to withdraw from the ABM Treaty, a test of the new booster had to be aborted and the missile destroyed in flight for safety reasons because it flew off course. Flight intercept tests that were to have used the new booster have come and gone without it. Indeed, development of the booster is so far behind that the Pentagon recently issued another contract for a competing design.

Equally problematic is uncertainty over how the system will track enemy missiles in flight and distinguish targets from decoys. One approach is to use high-power radars operating in the X-band (that is, at a frequency of about 10 billion cycles per second). A prototype X-band radar on the Kwajalein Atoll has been part all of the ground-based midcourse flight intercept tests so far, and technically, X-band radar progress has been one of the most successful developments in missile defense technology.

A year and a half ago, Lieutenant General Kadish testified to Congress that establishing an X-band radar in Alaska was the “long pole in the tent” for missile defense. This meant that the X-band radar was critical to a ground-based midcourse system and that if that radar was not built soon, the program would start slipping day for day. Then, as now, there were many other developments that would take as long or longer than building an X-band radar at Shemya, but the Pentagon’s official position was that construction needed to start in the spring of 2001 at the latest. Nevertheless, Clinton deferred taking action on the radar.

Surprisingly, the Bush administration has not requested funding for an X-band radar at Shemya in either of its first two budgets. This may be because the administration views such an installation as inconsistent with the ABM Treaty, which the administration has said it will not violate while the treaty is still in effect. Or the administration may not have requested funding because the Missile Defense Agency has been exploring “portable” X-band radars—that is, X-band radars deployed on ships or barges.

Some defense analysts believe that the Space-Based Infrared Satellite (SBIRS) program could be used in place of the X-band radar to assist a national missile defense. SBIRS—which would consist of two sets of orbiting sensor satellites, SBIRS-high and SBIRS-low—is designed to detect the launch of enemy ballistic missiles and could be used to track and discriminate among them in flight. However, the program has significant technical problems.

SBIRS-high, which will consist of four satellites in geosynchronous orbit and two satellites in highly elliptical orbits, is to replace the existing Defense Support Program satellites, which provide early warning of missile launches. A year ago, the SBIRS-high satellites were scheduled for launch in 2004 and 2006, but recently those dates have slipped roughly two years because of problems with software, engineering, and system integration. A year ago, realistic operational testing was scheduled for 2007; now, it may not occur this decade, which means that full deployment may not occur this decade. SBIRS-high is also well over cost and is in danger of breaching the legal restrictions covering cost growth.

SBIRS-low is to consist of approximately 30 cross-linked satellites in low-Earth orbit. A year ago, the launch of the first of these satellites was scheduled for 2006, but SBIRS-low has slipped two years because of a variety of difficult technical problems. The developmental testing program for SBIRS-low is very challenging, and realistic operational testing will probably not begin this decade. This could delay deployment of the full constellation of SBIRS-low satellites until the middle of the next decade. SBIRS-low is also dramatically over budget and was threatened with cancellation in the latest round of congressional appropriations.

For now, the administration has been saying that it will upgrade an existing radar on Shemya called Cobra Dane. Under this plan, the Cobra Dane radar would become an advanced early-warning radar with some ability to distinguish among targets. But the Cobra Dane radar operates in the L-band with about eight-times poorer resolution than a new X-band radar would have, raising questions about the effectiveness of any national missile defense using it.

In sum, the only element of a “layered” national missile defense that exists on anything but paper is the ground-based midcourse system pursued by the Clinton administration. Accordingly, it is nearly impossible to predict when, if ever, an integrated, layered national missile defense with boost, midcourse, and terminal phases might be developed. As noted above, given the most recent pace of testing, some part of the ground-based midcourse system could be deployed by the end of the decade or possibly by 2008.

However, the capability such a system would have would be marginal and probably would not be able to deal with many types of decoys and countermeasures or to cover much of the space through which an attacking ICBM might fly. The Bush administration has said it will deploy test elements as an emergency capability as early as possible, but such a deployment would be rudimentary and its capabilities would be limited to those already demonstrated in testing. It would likely not be effective against unauthorized or accidental launches from Russia or China, which might include missiles with countermeasures. It also would not be effective against launches from Iraq, Iran, or Libya since those countries are to the east, out of view of a radar on Shemya.


During the first year of the Bush administration, all U.S. missile defense programs—both theater and national—have slipped. In general, the shorter-range tactical missile defense systems are further along than the medium-range systems, and those medium- range systems are further along than the longer-range systems intended to defend the United States against ICBMs.

PAC-3 is the most developmentally advanced of any U.S. missile defense system, but full deployment will not likely take place before 2005, and realistic operational testing will continue for many years after the first Army units are equipped in the field. The THAAD program has slipped two years or more and will not be deployable until 2010. The Navy Area Wide program has been cancelled, and the Navy Theater Wide program has slipped two years or more and will not be deployable in a tactical role until the end of the decade. If the Pentagon restructures the program so that its priority is boost-phase or midcourse defense against strategic missiles, it will likely take longer. The Airborne Laser has slipped one year and will probably not be deployed as a theater missile defense before the end of the decade.

SBIRS-low has slipped two years and doubled in cost and probably will not be deployed before 2008.
For all practical purposes, national missile defense is technically not much closer than it was in the Clinton administration. There have been no flight intercept tests of the boost-phase or terminal-phase elements suggested by the Bush administration, and developmental testing could take a decade or more, depending on the pace of testing and the level of success in each test. The only element that can be flight-intercept tested against strategic ballistic missiles today is the ground-based midcourse system. Part of that system could be deployed by 2008, but elements fielded before then will have only a limited capability.

Thus, while making foreign policy, the Bush administration would do well to consider that probably only a limited-capability version of PAC-3 will be fielded during its tenure and that an effective, layered national missile defense will not be realized while it is in office. It would make little sense to predicate strategic decisions on a defense that does not exist.

It is important for Congress and the American public not to be frightened into believing that the United States is—as some missile defense proponents like to assert—defenseless against even a limited missile attack by a “rogue state” such as North Korea. Powerful and effective options exist, both military and diplomatic.

In Afghanistan, U.S. attack operations with precision-guided weapons have been highly effective. Those same precision weapons would be effective against an enemy ICBM installation. In fact, given current capabilities and the ever-improving technologies for precision strike, it would be fantasy to believe any national missile defense system deployed by 2003 to 2008 would work better and provide greater reliability at a lower cost than the precision-guided munitions used in Afghanistan.

On the diplomatic front, in 1999 former Secretary of Defense William Perry made a series of trips to convince North Korea to stop developing and testing long-range missiles. He was remarkably successful. Although Secretary Perry would not say that North Korea was no longer a threat, it was obvious that the North Korean threat had been moderated. Secretary of State Madeleine Albright was able to build on his trip the next year to secure a pledge from Pyongyang to halt flight testing of missiles. Dollar for dollar, Secretary Perry has been the most cost-effective missile defense system the United States has yet to develop. The most straightforward route to missile defense against North Korea may be through diplomacy, not technology.

Many decision-makers in Washington—and, from what one reads, the president himself—seem to be misinformed about the prospects for near-term success with national missile defense and the budgets being requested for it. It takes 20 years to develop a modern, high performance jet fighter, and it probably will take even longer to develop an effective missile defense network. Taking into account the challenges of asymmetric warfare, the time it can take to develop modern military equipment, the reliability required in real operational situations, and the interoperability required for hundreds of systems and subsystems to work together, it would be highly unrealistic to think that the United States can deploy an effective, layered national missile defense by 2004 or even by 2008.

In the meantime, policymakers should be careful that U.S. foreign and security goals and policies are not dependent on something that cannot work now and probably will not work effectively for the foreseeable future. A case in point is President Bush’s decision to abandon the ABM Treaty with Russia. That decision was certainly premature given the state of missile defense technology and likely could have been avoided or postponed for many years if not indefinitely.

This is not to say that missile defense technology ought not to be pursued—only that it should be pursued with realistic expectations. Policymakers must be able to weigh the potential merits and costs of missile defense based on a sound understanding of both the technology and the possible alternatives. No one weapon system can substitute for the sound conduct of foreign policy, and even a single diplomat can be effective on a time scale that is short when compared with the time that will be required to develop the technology for national missile defense.

Stages of Development

Missile defense, especially national missile defense, is the most difficult program ever attempted by the Department of Defense—much more difficult than the development of a modern jet fighter like the F-22 Raptor, the Navy’s Land Attack Destroyer (DD-21), or the Army’s Abrams M1A2 tank complete with battlefield digitization, endeavors that all have taken 20 years or more. Each new major weapons system must proceed through several stages of development, which are listed below. Most U.S. missile defense systems are currently in developmental testing and are therefore not close to deployment.

Research and Development (R&D): The period during which the concepts and basic technologies behind a proposed military system are explored. Depending on the difficulty of the technology and the complexity of the proposed system, R&D can take anywhere from a year or two to more than 10 years.

Engineering and Manufacturing Development (EMD): The period during which a system design is engineered and the industrial processes to manufacture and assemble a proposed military system are developed. For a major defense acquisition such as a high-performance jet fighter, EMD can take five years or more. If substantial difficulties are encountered, EMD can take even longer.

Developmental Testing: Testing that is performed to learn about the strengths and weaknesses of proposed military technologies and the application of those technologies to a new military system in a military environment. Generally, developmental testing is oriented toward achieving certain specifications, such as speed, maneuverability, or rate of fire. Developmental testing is conducted throughout the R&D and EMD phases of development and becomes more stressing as prototype systems evolve and mature.

Operational Testing: Testing that aims to demonstrate effective military performance against operational requirements and mission needs established for a system. Testing is performed with production-representative equipment in realistic operational environments—at night, in bad weather, against realistic threats and countermeasures. Military service personnel, not contractors, operate the system, which is stressed as it would be in battle. Operational testing of a major defense acquisition system typically takes the better part of a year and is usually broken into several periods of a month or two to accommodate different environments or scenarios. If substantial difficulties are encountered, several years of operational testing may be required.

Production: The phase of acquisition when a military system is manufactured and produced. Early on, during “low-rate production,” the quantities produced are typically small. Later, after successfully completing operational testing, a system may go into “full-rate production,” where the rate of production is designed to complete the government’s planned purchase of the system in a relatively short period of time, about five years.

Deployment: The fielding of a military system in either limited or large quantities in military units. The first military unit equipped may help develop tactics, techniques, and procedures for use of the new system if that has not already been done adequately in development.—P.C.

Flight Stages of Ballistic Missiles

All ballistic missiles have three stages of flight.

The boost phase begins at launch and lasts until the rocket engines stop firing and pushing the missile away from Earth. Depending on the missile, this stage lasts three to five minutes. During much of this time, the missile is traveling relatively slowly although toward the end of this stage an ICBM can reach speeds of more than 24,000 kilometers per hour. The missile stays in one piece during this stage.

The midcourse phase begins after the propulsion system finishes firing and the missile is on a ballistic course toward its target. This is the longest stage of a missile’s flight, lasting up to 20 minutes for ICBMs. During the early part of the midcourse stage, the missile is still ascending toward its apogee, while during the latter part it is descending toward Earth. It is during this stage that the missile’s warhead, as well as any decoys, separate from the delivery vehicle.

The terminal phase begins when the missile’s warhead re-enters the Earth’s atmosphere, and it continues until impact or detonation. This stage takes less than a minute for a strategic warhead, which can be traveling at speeds greater than 3,200 kilometers per hour.—ACA

Philip Coyle, a senior advisor at the Center for Defense Information, was assistant secretary of defense and the Pentagon’s director of operational test and evaluation from 1994 to 2001.


Pentagon Outlines Missile Defense Plans to Congress

Wade Boese

During congressional hearings held in late February and early March, top Pentagon officials sketched out U.S. ballistic missile defense plans for the first time this year, receiving a warm welcome from Republican lawmakers but a cooler reception from Democrats, who voiced concerns about the Bush administration’s $7.8 billion missile defense spending request.

Lieutenant General Ronald Kadish, director of the Missile Defense Agency, told senators and representatives at separate hearings that the Pentagon aimed to put missile defense capabilities “in play as soon as practicable,” with the goal of having limited protection against long-range ballistic missiles as early as 2004.

To accomplish this task, Kadish said the Pentagon would be willing to deploy prototypes and test assets if necessary and to add to or upgrade them as time passed, an approach the Pentagon describes as “spiral development.” Decisions to deploy test assets would depend on a number of factors, including the success of testing programs and the “international security environment,” according to the general’s prepared testimony.

Exactly which systems will be fielded remains undetermined because the current missile defense program calls for research and development without specific deployment plans. Appearing with Kadish at a March 7 hearing of the strategic subcommittee of the Senate Armed Services Committee, Edward Aldridge, undersecretary of defense for acquisition, technology, and logistics, told senators that “we don’t know what we’re going to buy.”

Yet the Pentagon does have ideas on what types of defenses it wants. In public statements and published excerpts of a secret January Pentagon report called the nuclear posture review, the Pentagon reveals it is hoping to have “near-term emergency [missile defense] capabilities” consisting of a single plane armed with a laser to shoot down missiles early in their flight, a rudimentary ground-based defense of five missile interceptors based in Alaska, and a single ship-based system that could attempt intercepting short- and medium-range ballistic missiles as they travel through space.

The nuclear posture review projects that beginning in 2006 the United States could deploy up to two or three Airborne Laser aircraft, four sea-based missile defense ships, and additional ground-based missile interceptor sites. By 2008 the Theater High Altitude Area Defense, a separate ground-based system that protects against short- and medium-range ballistic missiles during their last minutes of flight, might also be ready.

Because it claims to have no current procurement plans—aside from the Patriot Advanced Capability-3 system, which is currently being operationally tested and procured by the Army—the Pentagon did away with operational requirements documents (ORDs) for the missile defense program. These Pentagon papers define in advance what a system will look like and what capabilities it will have, and they set out specific criteria to determine if a system is ready to be purchased.

Describing the documents as “not appropriate” for missile defense at this stage, Aldridge defended the decision to do away with ORDs at a March 13 hearing of the strategic subcommittee of the Senate Armed Services Committee. He explained that, even if a potential system fell short of meeting a specific marker, such as hypothetically being able to intercept only eight missiles in six minutes instead of 10 missiles in five minutes, it could still add to a U.S. defense and should be considered for deployment with the aim of gradually improving its performance.

Once a particular missile defense system is transferred to one of the military services to procure and field, however, ORDs will be drawn up, according to Pentagon officials.

While Republicans in both legislative chambers commended the Pentagon on its efforts, many Democrats challenged whether missile defense funding could not be better spent on other programs that defend against more urgent threats, such as terrorist attacks, and if the Pentagon approach could lead to deployment of systems unable to do their job.

At a February 27 joint hearing of two subcommittees of the House Armed Services Committee, Representative Marty Meehan (D-MA) criticized the Pentagon’s proposed spiral development approach as last being used by the Soviet Union and condemned it as a “buy first, think later” acquisition policy. Although describing missile defense efforts as “valid,” Meehan expressed concern that the Bush administration was “shortchanging the war on terrorism” for missile defense spending.

Senator Jack Reed (D-RI) shared similar worries at the March 13 hearing. He told Pentagon officials that their approach of fielding systems and then adding to them might invite the Pentagon to “dumb down standards.”

A Democratic staffer on the House side summed up congressional reactions to the hearings as being in the “eyes of the beholder.” He said that the lack of detailed Pentagon plans makes it very difficult to tell American taxpayers what they are getting for nearly $8 billion a year in missile defense spending. He also noted that the first strategic defenses are scheduled to be available in 2004, which happens to be when the next presidential election takes place. “This is purely a political deployment,” the staffer asserted.

Congressional Budget Office Projects Missile Defense Costs

Wade Boese

Fulfilling a research request made by senior Senate Democrats last year, the Congressional Budget Office (CBO) released a report January 31 estimating that separate ground-, sea-, and space-based missile defenses would each cost tens of billions of dollars to complete.

The nonpartisan CBO reported that deploying a ground-based defense would total $23-64 billion between 2002 and 2015, depending on the number of missile interceptors involved. A stand-alone sea-based system would run $43-55 billion to reach operational capability by 2015, and an independent space-based laser system would cost approximately $56-68 billion between 2002 and 2025. The $7-9 billion already appropriated for the ground- and sea-based systems between 1996 and 2001 was not included in the CBO numbers.

Once the systems are deployed, CBO predicted that the annual cost for operating a ground-based defense of 100 missile interceptors after 2015 would be about $600 million, while upkeep of such a system numbering 375 missile interceptors would be around $1.4 billion. Maintaining a sea-based system after 2015 would cost about $1 billion per year, and keeping a space-based laser system functioning after it was deployed by 2025 would require an estimated $300 million each year.

The Bush administration is seeking to deploy layered missile defenses that might include all of these systems in order to maximize the chances of shooting down a ballistic missile during its entire flight. CBO warned against adding the separate figures together to arrive at an overall price tag for a layered system because, if deployed together, the systems could share some components, sensors, and research and development, thereby cutting costs.

CBO also expressed difficulty with calculating missile defense costs in general, claiming there was “substantial uncertainty” between existing programs and what the Bush administration might ultimately deploy. In addition, the report stated that “no detailed deployment plans or schedules exist” for most of the systems that CBO was asked to assess.

CBO offered no cost estimates for two systems, a sea-based boost-phase system and a revived “Brilliant Pebbles” system. CBO explained that it could not make a “credible” estimate on the sea-based boost-phase system because it was still in a “conceptual stage,” and it reported that the Ballistic Missile Defense Organization claimed in June 2001 that there were no plans to “reconstitute” the Brilliant Pebbles program, an initiative proposed by the first Bush administration that called for deploying 500-1,000 missile interceptors in space. But the CBO report also noted that the current administration is researching space-based interceptors and wants to conduct a space-based test around 2005 or 2006.

Responding to the report on January 31, Senators Tom Daschle (D-SD), Kent Conrad (D-ND), and Carl Levin (D-MI) called on the Bush administration to provide “detailed information on its missile defense plans” so Congress could compare missile defense costs with other defense programs. The senators worried that pursuit of such “costly” systems could divert funds away from programs aimed at countering threats they said are more likely and urgent than a ballistic missile attack.

Pentagon Puts Off Missile Defense Testing, Citing ABM Treaty

Wade Boese

Secretary of Defense Donald Rumsfeld announced October 25 that the Pentagon had decided against carrying out October and November missile defense testing activities that he said could be viewed as violating the Anti-Ballistic Missile (ABM) Treaty.

According to Rumsfeld, the Pentagon “decided not to go forward” with plans to use Aegis ship-based radars to track the target and interceptor in an October 24 test of the midcourse strategic missile defense system or to track a rocket being used to launch a satellite November 14. The secretary said a plan to use a radar at Vandenberg Air Force Base in California to track the target missile in the October 24 intercept test had also been dropped.

The ABM Treaty bans development, testing, and deployment of sea-based components and systems for strategic ballistic missile defenses. The same prohibitions apply to air-, space-, and mobile land-based systems as well. The accord also limits radars that can be used in testing strategic defenses to those that have been solely designated for such a role, which the California-based radar is not.

The intercept test and the satellite launch will still take place; they will simply be conducted without inclusion of the ship-based and California-based radars, which were added to the test program sometime after the main tests had been scheduled. It is uncertain when Pentagon planners requested using the radars to track targets—Pentagon and White House spokespersons either did not respond to inquiries or said that they did not know.

It is also unclear why Rumsfeld announced the delay of the October 24 test the day after it was supposed to have taken place—particularly since the Pentagon had already announced a few weeks earlier that the October 24 intercept would not take place until late November or early December. That delay had been caused by pre-test inspections and preparations, not anything treaty-related, according to a spokesman for the Ballistic Missile Defense Organization (BMDO), which oversees U.S. missile defense programs.

When asked by a reporter October 29 whether his announcement had been “somewhat incomplete” for failing to mention that the test had already been delayed for technical reasons, Rumsfeld replied, “Well, if it was, I’m sorry.” The secretary, however, went on to say that “the important thing is that we are not using one radar on [the test]” because of treaty concerns.

However, it is unclear what purpose in the test the Aegis radar, which is not part of the strategic midcourse missile defense system, would have served. A Pentagon report released last March stated the Aegis radar is “not capable of supporting [strategic]-class engagements due to its limited detection and tracking range.” The BMDO spokesman explained that Pentagon testers simply wanted to “see what the radar can do.”

The timing of Rumsfeld’s announcement, sandwiched between the October 21 meeting of President George W. Bush and Russian President Vladimir Putin and the two leaders’ upcoming mid-November summit, appeared designed to serve two purposes.

The test cancellations seemed to be a goodwill gesture toward Russia that Washington would hold off on any potential treaty-busting tests while discussing with Moscow what to do about the ABM Treaty. At the same time, the move suggested time was running short to reach an agreement on the treaty’s future because the accord is already hobbling the Pentagon’s missile defense testing that it claims is necessary.

That the Bush administration’s proposed testing program would raise treaty compliance issues was not unexpected. Missile defense planners were told to ignore ABM compliance concerns, according to two senior defense officials in a July 11 background briefing, and foreign governments were told by the United States in July that there is “no intent to design tests to conform to, or stay within the confines of the [ABM] Treaty.”

In fact, in July 17 Senate testimony, Deputy Secretary of Defense Paul Wolfowitz volunteered that adding a ship-based radar to a strategic missile defense test could conflict with the treaty, though he assured attending senators that the United States would not violate the treaty.

In his October 25 briefing, after noting that the Pentagon had been telling Congress and Russia “for some time now” that the U.S. missile defense program would “bump up against” the treaty, Rumsfeld declared, “That has now happened.” He asserted that this “reality” should serve as an “impetus” for the two presidents’ three-day discussion, which begins November 13 and is expected to focus on missile defenses, the ABM Treaty, and strategic nuclear cuts.

Since early this summer, Bush and other top administration officials have been trying to persuade the Kremlin to abandon the ABM Treaty so the United States can freely test and build national or strategic missile defenses. If unsuccessful, Bush has said the United States would unilaterally withdraw from the accord, which requires a six-month notice. For his part, Putin has rejected scrapping the treaty but has hinted that Russia would be open to amending it.

Two other possible missile defense activities identified by Wolfowitz in his testimony could also soon run afoul of the ABM Treaty. The first involves a missile intercept test next February that would involve both ABM and air defense radars operating concurrently, and the second is the start of construction next spring of a new Alaska-based missile defense test site, including five new missile interceptor silos. These activities have not been postponed or cancelled, and Rumsfeld did not say whether any final determination has been made about whether they would violate the treaty or not.

PAC-3 Ready for Action

On September 26, the Army declared that a “limited number” of Patriot Advanced Capability-3 (PAC-3) missiles were available for deployment. The PAC-3, which is designed to destroy short- and medium-range ballistic missiles, cruise missiles, and aircraft by colliding with them, is the first hit-to-kill anti-missile system ready for operational use.

The PAC-3 system has been under development for several years. The announcement that the missiles were available for deployment had been scheduled in advance for some time and was not connected with the events of September 11.

Army spokeswoman Captain Amy Hannah would not comment on how many PAC-3 missiles were available or when and where they could be deployed. Hannah said Lockheed Martin, the company that produces the PAC-3, recently transferred the missiles to the Army.

A Lockheed Martin spokesman declined to discuss the issue, citing a letter sent October 2 by Edward Aldridge, undersecretary of defense for acquisition, technology, and logistics, to private contractors. The letter asked companies to exercise “discretion” when speaking publicly about “statistical, production, contracting and delivery information” because such information could be useful to foreign intelligence collectors.

On October 19, the PAC-3 successfully completed its final intercept test in the developmental stage of its testing, which works out hardware and software bugs and refines a weapon system. During the developmental tests, the PAC-3 missed only once, hitting nine out of 10 targets. Now the PAC-3 will move forward to operational testing and evaluation, which is more representative of actual tactical conditions. For example, real soldiers, not testing personnel, operate the weapon during operational testing.

Currently, the PAC-3 is in low-rate production, but a decision is set to be made in September 2002 whether it should be moved to full-rate production. It is standard practice to keep a weapon system in low-rate production while testing is still being conducted.

The Continuing Impact of the Nuclear Revolution

Wolfgang K. H. Panofsky

The advent of nuclear weapons with their tremendous increase in destructive force decisively shifted the balance between offensive and defensive forces. This change has profound implications in judging the wisdom of any plans to deploy defenses against ballistic missiles carrying nuclear warheads.

The history of warfare is replete with competition between offense and defense, from the sword and the shield to the struggle between assault troops and fortifications. World War II provides lessons on the relative effectiveness of offense and defense. The French attempted to erect an impenetrable defense in the form of the Maginot Line against Germany, only to have Adolf Hitler’s mobile armored forces circumvent the defenses by taking a more northerly route. An innovative offense defeated a static defense. In the Battle of Britain, Hitler’s Luftwaffe carried out repeated massive attacks against Britain. However, each mission suffered losses on the order of 10 percent, inflicted by the Royal Air Force, which was assisted by radar, a newly introduced technology, and cryptography, which together yielded warning of such attacks. As a consequence, the attacking forces were reduced by a third for each 10 sorties flown, a level of attrition that proved unacceptable. History contains many such examples of both successes and failures of defenses against conventional attacks.

Nuclear weapons, however, profoundly changed the relationship between offense and defense because they increased the explosive power of a payload of a given weight and size by a factor of one million—a very profound change indeed. The demands on the performance and reliability of defenses against an attack by even a single missile carrying a nuclear weapon must therefore be extremely high for the defense to be considered effective. When the Germans attacked Britain during World War II with primitive ballistic missiles, none were intercepted, but the damage was limited because the missiles carried conventional explosives. Had they carried nuclear warheads, a single missile would have devastated London. Defense against ballistic missiles is therefore a totally different problem depending on whether such missiles carry conventional or nuclear payloads.

Against this background, national missile defense has re-entered the national and international political agenda. The Anti-Ballistic Missile (ABM) Treaty, signed in 1972, explicitly forbids deployments of defenses that protect the entire territory of signatory nations against strategic ballistic missiles. The basis of this treaty was the mutual recognition during the Cold War that the United States and the Soviet Union had attained a strategic balance based on deterrence: neither side could launch a nuclear attack against the other without incurring the risk of a retaliatory strike that would produce unacceptable damage. To appreciate the extent of the potential destruction, it should be remembered that the combined yield of the two nuclear weapons that killed 250,000 people in Hiroshima and Nagasaki would equal only about one-tenth the yield of a single nuclear weapon in today’s arsenal.

At the height of the Cold War, the United States and Soviet Union deployed more than 60,000 nuclear weapons in aggregate. Today the number of nuclear weapons in the world has shrunk by about one-half, with the overwhelming majority in the hands of Russia and the United States. At the same time, the so-called rogue states still have no nuclear weapons, although North Korea may have enough plutonium for one or two.

Nuclear weapons can be delivered to the U.S. homeland in many ways, of which the intercontinental ballistic missile is only one and the one requiring the most technological prowess. Nuclear weapons can be dropped from airplanes of almost any size, delivered by cruise missiles traveling in the earth’s atmosphere, detonated on ships in US harbors, or even smuggled across land borders. The United States has no significant homeland air defense, and its borders are notoriously porous, as witnessed by the largely ineffective “war on drugs.” Thus, a ballistic missile defense, even if it succeeded, would address only one avenue for the delivery of nuclear weapons. Moreover, rogue states are unlikely to adopt long-range missiles as their choice for nuclear weapons delivery because of cost and because the origin of the missiles is unambiguously traceable.

This was the situation during the Cold War, and this is the situation that remains today. The argument that deployment of a national missile defense could decrease US security is not a “relic of the Cold War” and does not reflect “Cold War thinking.” The United States’ vulnerability to delivery of nuclear explosives remains a fact that is difficult, if not impossible, to remedy by technical measures as long as nuclear weapons remain in the arsenals of the world.

The debate over missile defenses is complicated by the fact that ballistic missiles vary in range and can be used to attack military facilities and troop concentrations with conventional warheads. Theater missile defense (TMD), intended to defend smaller areas against short- to medium-range missile attacks, could be useful in defending US troops or military facilities against conventional attacks, whose impact could be significantly blunted by even partially effective defenses. This situation contrasts sharply with the use of defenses against nuclear warheads, where leakage of even a single nuclear warhead would have disastrous effects.

The ABM Treaty does not deal with TMD because the treaty’s intention is to preserve strategic stability, and it is expected that TMD would be used chiefly in battlefield situations against missiles armed with conventional warheads. (The situation is complicated by the fact that in the case of defense of small nations, such as Taiwan, Israel, or even Japan, TMD could be perceived as providing a defense for the entire territory.) In 1997 the United States and Russia negotiated a demarcation agreement that defined the boundary between permitted and forbidden anti-missile deployments as measured by the character of the interceptor and the speed of the target to be intercepted. The demarcation agreement, however, has not as yet been formally submitted to the Senate for ratification, and it remains mired in congressional politics around the future of the ABM Treaty.

Clearly, the demands on the performance of missile defenses against nuclear weapons are extremely high. The question therefore becomes, do we have the technology needed to achieve this level of effectiveness? The table below illustrates the alternative means by which interceptors can destroy ballistic missiles. Each one of these approaches has its strengths and weaknesses. The table is divided into columns that delineate when the intercept of the incoming ICBM is to occur: during the boost phase, the time during which the missile booster is still burning; in midcourse, when the attacking missile is traveling outside the atmosphere; and after re-entry, once the offensive missile is approaching its target within the atmosphere.

In addition to the different locations of intercept, missile defenses can employ a variety of technologies. The interceptor can be guided by sensors employing radar or using infrared detectors registering thermal emissions from the target warheads. Sensors can be based on land, placed on aircraft, or deployed on orbiting satellites. The interceptor can destroy the incoming ICBM in a number of ways: by direct impact (hit-to-kill), by fragmentation of an explosive warhead, or through a nuclear detonation.

Boost Phase

Boost-phase intercept defenses have never been developed but are now apparently under serious consideration. During the boost phase, an ascending missile emits extremely intense infrared radiation, and therefore no decoy other than another booster can simulate a missile during this period of its trajectory. However the boost phase is very short, no longer than three minutes, and takes place near the launch site. A boost-phase interceptor must therefore be forward-based on a ship or aircraft or on friendly territory. Alternatively, coverage could be provided from space, but a large number of satellites would be required for such coverage to be continuous.

Boost-phase intercept faces several problems. A decision to intercept on receipt of a putative signal indicating an ICBM launch has to be made in an exceedingly short time and may be subject to error. Additionally, the forward-basing requirement means that either the ships or aircraft that launch the interceptor are vulnerable to attack themselves. Moreover, most potential inland launch sites cannot be covered at all from sea or air. This disadvantage could, of course, be considered an advantage if the United States wanted to signal that the ABM system is intended solely to neutralize a rogue state, like North Korea, and is not capable of defending against inland launch from either Russia or China. Because boost-phase defenses intercept the ICBM before it can disperse a fragmented payload, they would also be effective against a missile that carried small multiple payloads, such as “bomblets,” which, although too small for nuclear weapons, might carry biological warfare agents.

Midcourse Intercept

Intercept while an enemy’s ICBM travels in the vacuum of outer space permits more decision time to commit an interceptor. However, its weakness is that, because light and heavy objects follow identical trajectories in the vacuum of outer space, the offensive ICBM could employ a number of techniques to deceive the intercept vehicle. For example, a substantial number of lightweight decoys could be deployed in parallel with the real warhead, making it difficult for the interceptor to discriminate between them. Such lightweight decoys can be designed to simulate the thermal emissions from the real warhead and even the fluctuation in such emissions or variations in reflected light caused by the warhead’s motion. Alternatively, the offense could employ “anti-simulation” countermeasures, in which the real warhead is enclosed in a light balloon, making it indistinguishable from a number of accompanying decoy balloons. Also, should the offense employ many small bomblets, the defense would have to attack each of the bomblets, which in practice would be impossible.

Terminal, or Reentry, Defense

Once the offensive missile’s payload is re-entering the atmosphere, it faces drag, which would distinguish lightweight decoys from the heavy warhead. Thus, the principal countermeasure available to the entering warhead would be to maneuver, hoping that the interceptor cannot keep up with such motions. However, terminal defense can only defend a limited area, and it would be ineffective against bomblets that could result in a very large number of identical entering targets.

The Clinton administration pursued plans for midcourse intercepts with the interceptors initially based at a single location. The initial ICBM trajectory was to be tracked by infrared sensors placed on orbiting satellites, followed by tracking by ground-based radars. Final hit-to-kill guidance was to be provided by infrared seekers located on the intercept vehicle itself. Ideally, the Clinton defense sought to cover the entire United States but would have left US allies unprotected. During the presidential campaign, the Clinton defense was opposed—and rightfully so—because of its vulnerability to decoys and fragmented warheads.

Moreover, since the Clinton defense was designed to defend only the United States, US allies heavily criticized the plans because they would have been left exposed as potential hostages to enemy attack and because they were concerned with the anticipated highly negative reaction of Russia and China. President Bill Clinton decided not to deploy the system after determining that, of his four criteria for deployment—technical readiness, a demonstrated threat, cost, and impact on relations with other states—neither adequate technical readiness nor acceptance by other nations had been achieved.

President George W. Bush reaffirmed his campaign commitment to the concept of a national missile defense in his speech on May 1, but he remained silent on how this goal is to be accomplished technically. The words the administration often uses are “multilayered defense,” meaning that the system would combine several of the basic options given in the table on the previous page, with emphasis given to boost-phase intercept. The cost of a multilayered defense would be much larger than the estimated $60 billion the Clinton defense would have cost. Accepted designs for the architecture of such a defense do not exist, and the wisdom of going forward with such a defense hopefully will be critically examined during the strategic review that the administration is now conducting.

Research and development on missile defenses has been pursued for decades at an accumulated cost of some $100 billion in today’s dollars. Nevertheless, the technical status of such defenses is such that the plans outlined by the president in his speech could not become reality during the next two presidential terms.
All ballistic missile defenses against nuclear weapons delivery result in an unfavorable exchange ratio relative to the offense. In other words, should the United States decide to deploy such defenses to reduce the vulnerability of this country, an adversary could increase or modify its offensive forces at a drastically lower cost and in a way that would leave the United States just as vulnerable. Thus, deployment of a US national missile defense, should a capable adversary nation such as China or Russia decide to respond by enhancing its strategic nuclear force, would simply escalate arms competition to higher levels of potential violence without actually protecting the United States.

Such an unfavorable exchange ratio may not be a sufficient argument against deploying missile defenses against rogue states, such as North Korea, which might not be able to afford to counteract such defenses even at moderate cost. It has therefore been difficult for some national leaders to reject proposals to defend their countries against possible threats from potential adversaries “of concern” or from unintended releases of a small number of nuclear-tipped missiles from any country.

For instance, under congressional pressure, President Lyndon Johnson proposed the Sentinel system to defend US cities against then-rogue-state China. But President Richard Nixon, recognizing the escalatory nature of the Sentinel system and a comparable Soviet system, negotiated the ABM Treaty and converted the Sentinel hardware to the terminal defense of US Minuteman missile sites. This system, called Safeguard, was eventually deployed at one site as permitted by the ABM Treaty, but operation was discontinued after less than one year once its limited effectiveness in relation to its operational cost was recognized.

The Clinton defense was designed to “walk the tightrope” by defending the nation against the ballistic missiles from today’s rogue states—North Korea, Iran, and Iraq—and stopping accidental launches from Russia and China, while ostensibly not being sufficiently robust to blunt the deterrent forces of Moscow and Beijing. But China, Russia, and US allies did not find this limited objective credible.

In view of all the basic facts, the financial, political, and strategic costs outweigh the benefits of the limited protection a national missile defense could offer. An honest acknowledgment by the US leadership that technical means to prevent hostile nuclear detonation on US soil do not exist and are not in the offing would go a long way toward providing a realistic and honest basis for discussion on a national missile defense.

All the technical and economic facts concerning ballistic missile defense, combined with the availability of delivering nuclear weapons by means other than ballistic missiles, lead to an inescapable conclusion: In the nuclear weapons age, the world is condemned to live in an offense-dominated condition. That means that defenses cannot protect the United States from nuclear weapons. That goal has to be attained by dissuasion, where dissuasion means a combination of diplomacy and deterrence. Diplomacy must convince a potential adversary that its security will decrease rather than increase by acquisition and delivery of nuclear weapons, while deterrence implies that the US response would be unacceptable to the adversary if it crossed the nuclear threshold by actually using such weapons. Dissuasion has been effective for 55 years—notwithstanding the eruption of roughly 100 armed conflicts in that time, a tradition of “non-use” of nuclear weapons has prevailed since they were first employed against Japan.

Should this administration now decide to deploy missile defenses to protect the United States? Today there is nothing to deploy, and no system can be in place before the Bush administration leaves office. Thus, the current debate over missile defenses is a house of cards built on a nonexistent technical foundation. Other nations should not immediately feel militarily threatened by a deployment decision, but such a decision would de facto abrogate the ABM Treaty and would place the entire arms control structure in jeopardy. Such a decision would profoundly and negatively affect political relations with Russia and China, as well as with NATO and the rest of the world. In particular, should China respond to US deployment plans by augmenting its now limited long-range missile force, both qualitatively and quantitatively, first India and then Pakistan are likely to respond in kind. US security would be diminished.

The revolution in warfare caused by the advent of nuclear weapons cannot be reversed. Scientific and technical facts cannot be coerced by policy. Defense of the nation, however well-intentioned, cannot be achieved by scientifically unsound means. President Bush should reconsider his approach to national missile defense and await the outcome of a balanced and thorough analysis of the fundamental issues.

Intercept Options
Stage at which ICBM is intercepted
Boost Phase
Very difficult
Easy decoys
Maneuvering target
Interceptor launch location
Forward presence or space
Flexible, depends on range
Near defended area
Vulnerability of interceptor launcher
Generally large
Generally small
Decision time to commit to intercept
Less than three minutes
15-30 minutes
About 30 minutes
Effectiveness against fragmenting warhead
Very limited

Economic exchange ratio of defense if ICBM carries nuclear warhead


Wolfgang K. H. Panofsky is director emeritus of the Stanford Linear Accelerator Center in California.

Pentagon Report Highlights Hurdles for Missile Defenses

Wade Boese

In its latest annual report, released March 2, the Defense Department's office of operational test and evaluation expressed strong concerns about the testing program for the U.S. national missile defense (NMD) system and highlighted several technical challenges confronting U.S. theater missile defenses. The review office also disputed the contention that a sea-based theater missile defense currently under development could be simply or quickly modified to defend against strategic ballistic missile attacks.

As part of its annual assessment of all Pentagon weapons testing programs, the office of operational test and evaluation reviewed the Pentagon's several ballistic missile defense programs, all of which are still proceeding under the Bush administration. The completed evaluations buttressed Lieutenant General Ronald Kadish's common cautionary refrain about the difficulties of building missile defenses, that "this is rocket science." Kadish is director of the Ballistic Missile Defense Organization (BMDO), which oversees U.S. missile defense programs.

Designed to protect all 50 U.S. states from strategic ballistic missile attacks by intercepting warheads as they cruise through space, NMD is the most high profile of the missile defense programs. The system will initially consist of 20 ground-based missile interceptors deployed in Alaska supported by advanced radars and eventually two new satellite constellations.

In its evaluation of the NMD program, the review office noted that the system represented only a "limited functional representation of the objective system" because only prototype and surrogate NMD elements were being tested. For example, none of the five flight tests to date, three of which have been intercept attempts, have employed the system's planned actual booster, which is still under development.

Earlier this year, BMDO projected the booster's first flight test, previously scheduled for early last year, could happen as soon as March, but a BMDO spokesperson said March 23 that the test will not take place before August because of additional design and material changes to the booster. The number of solo flight tests of the booster scheduled before it is used in an actual intercept attempt has also been trimmed from three to two.

The NMD test program, according to the Pentagon review office, is "not aggressive enough to match the

pace of acquisition to support deployment and the test content does not yet address important operational questions." Specifically, the office did not feel that the flight testing is realistic enough with regard to intercept altitudes and closing velocities. It also asserted that the decoys planned for deployment with the targets in future testing are too simple and noted that established nuclear powers already use countermeasures that are more sophisticated. BMDO responded that it was exploring options to make the testing more stressful.

Aside from flight tests, the review office pointed out that a key tool for running simulations of intercept scenarios that cannot be flight-tested was delivered late and not fully developed, thereby preventing it from being used in any "significant" way. In addition, the office faulted integrated ground tests of NMD system elements as being "unrealistic" because of simplification and the low number of objects used in testing scenarios.

The report recommended that, when assessing system performance, more weight should be given to the discrimination capabilities of the system's radars and the exoatmospheric kill vehicle (EKV), which is designed to seek out and collide with an incoming warhead in space. Ultimately, the EKV's ability to discriminate will be the "biggest challenge" for the NMD system to work properly, according to the evaluation. All other NMD tasks appear to be technologically possible, the report stated.

The review office declared that any successful intercept would be a "significant achievement" but cautioned the success would need to be viewed within the context of the testing program's limitations. Of the three NMD intercept tests, the first resulted in an intercept while the last two failed.

Theater Missile Defenses

In addition to the proposed NMD system, the United States is also developing defenses to protect deployed U.S. forces from attack by slower and shorter-range theater ballistic missiles. Not counting laser-based and cooperative defenses, the Pentagon is working on four different theater missile defense systems: Theater High Altitude Area Defense (THAAD); Patriot Advanced Capability-3 (PAC-3); Navy Area Theater Ballistic Missile Defense (NATBMD); and Navy Theater Wide (NTW).

A mobile ground-based system intended to intercept incoming theater ballistic missiles inside and outside the atmosphere during their mid-course and early terminal phases, the THAAD system experienced six straight intercept failures, starting in December 1995, before achieving two successive hits in 1999. While characterizing the THAAD program as having made "significant progress," the office of operational test and evaluation noted that the two intercepts demonstrated only a "limited integrated system performance."

The THAAD missile is now undergoing a redesign to address problems identified in the earlier flight tests. The missile's "reliability, testability, producibility, and affordability" must be increased, according to the Pentagon review office, and the entire system should be exposed to "extreme operating environments" to validate that it will work wherever deployed. The Defense Department is calling for five successful intercepts with the redesigned missile before moving further with the program.

Whereas THAAD is targeted at upper-tier threats, the PAC-3 system will be focused on lower-tier threats, such as cruise missiles, aircraft, and tactical ballistic missiles in their terminal stage. PAC-3 has achieved six intercepts in six attempts, but due to delays in software development and unexpected hardware problems, only one flight test involved what the review office deemed a "production representative" PAC-3 missile. Five of the successful intercepts were also conducted against what the review office described as "limited threat representative targets."

Moreover, other tests of the PAC-3 ground system revealed a number of "reliability" and "high priority" problems concerning difficulty in identifying, classifying, discriminating, and tracking targets. These problems must be fixed before the PAC-3 ground system is fielded, the report stated.

Largely built upon upgrades to existing weapons systems—mainly the Aegis combat system, which can track more than 100 targets simultaneously, and the Standard Missile, which is used for air defense—the NATBMD is a "technically solid" program, according to the review office. But the Navy has not conducted a live test to prove the system can acquire, track, and intercept a theater ballistic missile. The NATBMD system will be ship-based and is envisioned as protecting coastal cities and amphibious forces against short- to medium-range ballistic missiles.

While tests have shown that the Aegis system can track a ballistic missile, the review office cautioned that the system could have difficulty in simultaneously defending against ballistic missiles and performing its anti-air-war function. In addition, the complexity of upgrading the Aegis' Weapons System computer program may have been "underestimated" the report stated.

The proposed Navy Theater Wide system, which will be tasked with intercepting medium- and long-range theater ballistic missiles from the late ascent phase through the early descent phase, rests upon more substantial upgrades to the Aegis system and the Standard Missile. The review office expressed concern about the Aegis system's autonomous ability to perform the required detection and tracking functions, particularly its ability to locate a smaller target (when compared with airplanes, as the system was originally designed to track) at a much greater distance. Other potential problems are whether the infrared seeker on the NTW's warhead will be able to adequately discriminate between the target and debris and whether it could be blinded by its own propellant plume.

Although geared toward countering theater ballistic missiles, some missile defense advocates have suggested that NTW could be adapted or upgraded relatively easily to permit it to intercept strategic ballistic missiles in their boost phase, when the rocket engines are still burning. However, the review office asserted such a change in mission would require "major upgrades."

Citing the Aegis system's limited detection and tracking range for strategic ballistic missiles, the review office concluded the Aegis' radar is "not capable of supporting NMD-class engagements." The planned NTW Standard Missile-3 (SM-3), which just completed its first successful flight test involving all of its three stages in January, lacks the velocity needed for ascent-phase or mid-course intercepts and would need "major propulsion upgrades," according to the report. In fact, the SM-3's burnout velocity is less than half of what is needed to engage strategic ballistic missiles in mid-course trajectory. The review office also assessed the NTW kill vehicle's detection and divert velocity capabilities as being inadequate for "NMD endgame performance" and noted that the NTW warhead does not meet the NMD mission requirement of being "nuclear hardened."

Taken together, these "major shortcomings," according to the review office, led it to conclude that neither NTW nor even a five-year upgrade of the NTW system could be considered a "viable sea-based NMD option." The Defense Department is currently conducting a review of its ballistic missile defense options.


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