On June 19, Israeli military spokesman Brigadier General Effie Defrin mistakenly stated that the Israel Defense Forces had struck Iran’s Bushehr Nuclear Power Plant. Although Israel quickly walked this back, the comment triggered regional alarm: Oman circulated information to civilians on what to do in the event of a nuclear incident, Bahrain prepared 33 shelters in case of an emergency, and the Gulf Cooperation Council activated its Kuwait-based Emergency Management Centre. This reaction underscores a deeper concern quietly influencing the Israeli and U.S. campaign: how radioactive fallout risks shape the limits of military action against Iran’s nuclear program.
Russia and China have seized on the confusion, falsely asserting that the targeting of any nuclear site risks catastrophic contamination. While Moscow’s and Beijing’s claims exaggerate the risks, they also tap into legitimate concerns: Some nuclear targets do carry significant fallout risks. Understanding these risks can help explain both why Israel has avoided some sites and the challenge of completely dismantling Iran’s nuclear program militarily.
While contamination concerns are not the central driver of Israeli strategy toward Iran’s nuclear program, in the next stage of the conflict, they may increasingly influence Israel’s target selection, timing, and operational methods. Israel now has fewer viable military options left for striking Iran’s nuclear program. With U.S. and Israeli attacks targeting portions of Natanz, Fordow, and Isfahan, what remains are either sites like Bushehr—which carry high radiological risk—or the remaining hardened underground facilities at Fordow, which would demand significant escalation to neutralize.
When Preemption Was Simpler: Israel’s Historic Counterproliferation Strikes
Historically, Israel has both taken precautions to protect civilians and used environmental and contamination concerns to justify preventive strikes before neighboring nuclear programs went online, as evidenced by declassified documents from Israel’s attacks on the Iraqi and Syrian nuclear reactors in 1981 and 2007, respectively. During Operation Opera on Iraq’s Osirak reactor, Israeli Prime Minister Menachem Begin argued that waiting until the reactor was active would cause contamination. Similarly, a U.S. State Department memo highlights that the Israelis expressed the “desire to avoid the radiation problem which would have occurred once the reactor was charged.” In the 2007 strikes on the Syrian Deir ez-Zor reactor (Operation Orchard), Israeli officials cited the proximity to the Euphrates River as part of their rationale for attacking before it was operational. Although environmental concerns were a factor in both cases, fallout was avoided because preemption simplified the mission.
Today, dismantling the remainder of Iran’s nuclear program presents a more complex challenge: Its more sensitive facilities are already active, highly fortified (requiring heavier munitions), and striking with large quantities of radiological and chemical material does present genuine contamination risks. Operation Midnight Hammer, the June 21 U.S. strikes on Fordow, Natanz, and Isfahan, may represent the ceiling of what conventional force can achieve on Iran’s nuclear targets without triggering broader fallout. For Israel, this means that future operational phases would have to involve sites that are either more fortified, environmentally risky, or both. As the campaign moves forward, Israel will have to balance its goal of complete dismantlement with the potential for fallout in ways it has not had to before.
Evaluating Fallout Risks: What’s Been Hit, What’s Off-Limits, and What’s Left
The radiological and chemical risk from military strikes on Iranian nuclear infrastructure vary dramatically based on the type, operational status, fortification level, and dispersal potential of the facility (Table 1).
