Outer Space Treaty May Ban Strike Weapons

To the Editor:

In his excellent article on space arms control (ACT, April 2002), James Clay Moltz recommended five core provisions for a new, international space arms control agreement. We believe that the Outer Space Treaty of 1967 may already address the third and arguably most important recommendation: no stationing of strike weapons of any sort in low-Earth orbit, including kinetic kill vehicles and lasers.

The Outer Space Treaty was the second multilateral “nonarmament” treaty, following the model of the Antarctica Treaty of 1959. The Eisenhower administration, which negotiated the latter and laid down principles for the former, focused on the objective of prohibiting military competition in Antarctica and space before it occurred. A 1957 proposal by the Eisenhower administration, which was endorsed by Canada, France, and the United Kingdom, sought “to assure that the sending of objects through space will be exclusively for peaceful purposes.” This objective was then agreed internationally in a unanimous 1963 UN General Assembly declaration of legal principles, which stated that “the use of space shall be carried on for the benefit and in the interests of all mankind….”

The Outer Space Treaty was intended to implement this principle. Its first article says that the use of space “shall be carried out for the benefit and in the interests of all countries.” The only weapons it explicitly bans from orbiting around Earth are nuclear and other weapons of mass destruction because they were the primary concern in 1967. Indeed, the negotiating history shows that this prohibition focused on the immediate concern (i.e., nuclear) of the parties in the 1960s—stemming in part from the Cuban missile crisis—but that it did not obviate the broader peaceful-purpose principle of the 1957 proposal.

In fact, the Outer Space Treaty contains one overall rule: space shall be preserved for peaceful purposes for all countries. It requires any state considering activities that “would cause potentially harmful interference” with other states’ activities to undertake appropriate consultations. Similarly, other states may request consultations.

Further provisions for consultation were included to give the parties realistic opportunities to achieve post-1967 agreements on what the general provisions should mean in the future. For instance, if a state decided to test and possibly orbit in space an anti-satellite weapon (ASAT) utilizing a laser or kinetic kill vehicle, other states-parties to the space treaty could request consultations. They could conclude that the treaty prohibits the orbiting of the proposed ASAT. We believe that such an interpretation could be a permissible interpretation of the treaty. Indeed, space testing or deployment of other future strike weapons that are inconsistent with “the benefit and in the interests of all countries,” within the meaning of the Outer Space Treaty, might produce a similar interpretation.

The fact that in the 1970s and 1980s both the Soviet Union and the United States toyed with ideas for space weapons that were not weapons of mass destruction does not reverse the overall rule that space should be preserved for peaceful purposes for all countries. There was no agreement by the parties to the space treaty in the 1970s and 1980s to limit the broad rule on preserving space for peaceful purposes.

The parties to the space treaty could decide whether to adopt a position on Earth-orbiting ASATs as a formal interpretation, after a review of state practices since 1967 and the negotiating history of the treaty. Unanimity among parties is not required for any formal interpretations, but a large majority of parties adopting a particular position would be persuasive. Similarly, the United Nations, acting through its First Committee and then through the General Assembly (which recommended the Outer Space Treaty in the first place), could pass a resolution formally interpreting it. If there were significant dissent, pursuant to the UN Charter the General Assembly could request an advisory opinion from the International Court of Justice at The Hague confirming this interpretation.

Such an interpretation could not cover all missile defense basing options. For example, the Anti-Ballistic Missile (ABM) Treaty bans land- and air-based missile defenses. The Outer Space Treaty clearly does not deal with them. Furthermore, this interpretation could not prohibit nonstrike Earth-orbiting or geostationary communications or reconnaissance satellites that were well known and in use in 1967. Nevertheless, the interpretation could cover Earth-orbiting weapons designed to strike satellites or missiles. The almost 100 states that are party to the space treaty will have to decide whether they are prepared to seek such an interpretation.

George Bunn
General counsel to the Arms Control and Disarmament Agency during the Outer Space Treaty negotiations and director emeritus of the Arms Control Association and the Lawyers Alliance for World Security

John B. Rhinelander
Deputy legal adviser at the Department of State during the ABM Treaty negotiations, legal adviser to the U.S. SALT I delegation, Arms Control Association director, and vice chairman of the Lawyers Alliance for World Security