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Iran-Israel Tensions May Push Iran to Rethink Nuclear Arms
May 2024
By Kelsey Davenport
Iran closed its nuclear facilities to international inspectors the day after launching a barrage of drones and missiles at Israel and a senior military official said Tehran may rethink its prohibition on developing nuclear weapons if Israel retaliates by attacking the country’s nuclear infrastructure.
International Atomic Energy Agency (IAEA) Director-General Rafael Mariano Grossi said Iran reopened the nuclear sites on April 15, but he kept inspectors away for another day until the situation was “completely calm.”
The April 13 Iranian strike, which included about 300 drones and missiles, was calibrated carefully to allow Israel and its partners to shoot down most of the Iranian systems. But it opens a new chapter in Iran-Israel relations as Tehran signaled it will respond to future Israeli attacks by directly striking Israel rather than relying on proxies and partners in the region.
At the same time, Iran made clear that it does not wish to escalate the conflict with Israel. Iran’s UN mission said on April 13 that Tehran’s attack was a direct response to an April 1 Israeli strike on the Iranian consulate in Damascus that killed several high-level Islamic Revolutionary Guard Corps (IRGC) officers and that the matter is “now concluded.”
Although the United States assisted Israel in intercepting the Iranian drones and missiles, the White House said that U.S. President Joseph Biden made clear to Israeli Prime Minister Benjamin Netanyahu that Washington would not participate in any counterstrike against Iran.
Israel did retaliate for the attack on April 19 by striking several Iranian military sites, including targets near the city of Isfahan, which includes declared nuclear facilities. But Grossi said there was no damage to those nuclear sites. The scope of the attack was limited, suggesting Israel’s intention was to demonstrate to Iran its ability to strike targets deep within the country.
White House Press Secretary Karine Jean-Pierre responded to the Israeli strike by saying that the United States does “not want to see this conflict escalate” and that it is working to reduce that risk.
Before Israel’s counterattack, Ahmad Haghtalab, the IRGC commander in charge of security at Iran’s nuclear facilities, said that Israeli threats to strike the nuclear infrastructure “make it possible to review our nuclear doctrine and deviate from our previous considerations.”
Iran’s supreme leader, Ayatollah Ali Khamenei, has banned the development of nuclear weapons by religious decree. Nasser Kanaani, spokesperson for the Iranian Foreign Ministry, reiterated the prohibition in an April 22 press briefing, saying that “nuclear weapons have no place in our nuclear doctrine.” He said the country’s nuclear program is entirely peaceful.
But Haghtalab’s comments support assessments by western officials and experts that Tehran could rethink that prohibition and develop nuclear weapons if necessary for security.
Iran’s decision to bar access to its nuclear sites and the IAEA delay in resuming inspections suggest Tehran and the IAEA were concerned that Israel could respond to the April 13 attack by targeting Iranian nuclear facilities.
Grossi told reporters at the United Nations on April 15 that the agency is “always concerned” about the possibility of an Israeli strike and urged “extreme restraint.”
Some former U.S. and Israeli officials used the April 13 attack to urge Netanyahu to strike Iran’s nuclear facilities, despite the risk that such action would drive Iran to develop nuclear weapons. In an April 14 CNN interview, for instance, former U.S. National Security Advisor John Bolton suggested that Israel should “destroy Iran’s nuclear weapons program” in response.
Iran has the capability to develop nuclear weapons, but the country is not engaged currently in key weaponization activities, according to the U.S. intelligence community.
Israel periodically has sabotaged Iranian nuclear facilities and assassinated Iranian nuclear scientists, but it is unclear if the country is willing to risk a large-scale attack on the nuclear program without the support of the United States, particularly if there is no evidence that Tehran is developing nuclear weapons.
Logistically, it would be challenging for Israel to target some of Iran’s facilities using conventional weapons. Iran’s nuclear infrastructure includes deeply buried sites, such as the Fordow uranium-enrichment facility, that would necessitate the use of larger U.S. conventional bombs, such as the GBU-57 Massive Ordnance Penetrator, to destroy. Furthermore, without U.S. refueling support, it would be more difficult for the Israeli Air Force to strike Iran because of the distances between the countries.
A large-scale attack on Iran also increases the risk that Tehran will decide that nuclear weapons are necessary to deter future attacks, as Haghtalab suggested. Given that Iran already has the capability to develop nuclear weapons, setbacks from a military strike would be temporary because Iran has the knowledge necessary to reconstitute the program.
As heightened regional tensions and the possibility of an attack on its territory increase the risk of Iran determining that nuclear weapons are necessary, the April 14 decision to close its nuclear facilities demonstrates how the country could cite security concerns to block IAEA access and use the period between inspections to accelerate production of material for a nuclear bomb.
This risk is heightened because Iran has stockpiled enough uranium of near-weapons-grade quality for about three weapons and is operating centrifuges that enrich uranium efficiently. As a result of these advances, Iran can produce enough weapons-grade material for a nuclear weapon in less than a week.
Although the IAEA would detect weapons-grade enrichment after resuming inspections, the delay could provide Tehran with enough time to divert the weapons-grade uranium to a covert site for weaponization, a process that could take six months to a year.
Grossi did not appear concerned about the April disruption. He said it “has not had an impact on our inspection activity.” But he continues to raise concerns about the overall ability of the IAEA to monitor Iran’s nuclear program. In a March 29 interview with CNN, he warned that if Iran does not cooperate with the agency, the IAEA is approaching a point where it will not be able to give “a credible assurance that Iran’s nuclear program is entirely peaceful.” He said inspectors must have “full visibility.”