Nuclear Expert Deaths Raise Proliferation Concerns Amid US-Israeli Strikes on Iran

The elimination of Iranian nuclear scientists in recent US-Israeli military operations has sparked concerns about potential nuclear proliferation risks should the Tehran regime become destabilized. While Iran can replace personnel, security experts warn that the loss of specialized nuclear knowledge will be difficult to rebuild, potentially leaving sensitive materials and expertise vulnerable.

“Currently, the risk of nuclear terrorism or nuclear material moving to the black market remains low,” said Kelsey Davenport, director of nonproliferation policy at the Arms Control Association. “Non-state actors would face challenges in accessing enriched uranium, and it is unlikely they would have the infrastructure to enrich it to weapons-grade levels and convert it into the metallic form required for a warhead core.”

However, Davenport cautioned that should the current Iranian government collapse or experience significant internal instability, “there is an increased risk that nuclear materials will be stolen or diverted to undeclared sites.” She also highlighted concerns that Iranian nuclear scientists might be willing to sell their expertise to state or non-state actors seeking nuclear weapons.

The campaign against Iran’s nuclear infrastructure has claimed several high-profile casualties between 2025 and 2026. Among them was Hossein Jabal Amelian, head of the Organization of Defensive Innovation and Research (SPND), killed during Operation Rising Lion and Operation Epic Fury. SPND, widely considered the successor to Iran’s pre-2004 nuclear weapons program, plays a critical role in ongoing weaponization research.

Other key casualties from 2025 include Mohammad Mehdi Tehranchi, Akbar Motallebizadeh, and Said Borji, all reportedly linked to nuclear weaponization work.

“The full impact of this campaign on Iran’s weaponization capabilities remains unclear,” explained Jim Lamson, a senior research associate at the Center for Nonproliferation Studies and former CIA analyst. “There will be replacements of the managers and scientists, but the impact on the killed officials’ experience and expertise will be hard to replace.”

Lamson noted that scientists’ successors may also fear becoming targets themselves, potentially affecting “their motivation and willingness to participate in any nuclear weapons program.”

The experts killed were deeply embedded in sensitive aspects of Iran’s nuclear program, according to Lamson. “These scientists had expertise in areas of the nuclear fuel cycle of key concern for nuclear weapons, including the production of highly enriched uranium (HEU), which was Iran’s main pathway for fissile material,” he said.

Beyond targeting personnel, US and Israeli strikes have also damaged physical infrastructure critical to Iran’s nuclear ambitions. “We have identified at least 11 weaponization-related sites that have been hit since 2024,” Lamson revealed. These include SPND headquarters, a newly identified site called Min-Zadayi in northeast Tehran, explosives testing facilities, the Defense Ministry’s Shahid Meisami complex, and several research universities.

These targeted facilities were reportedly involved in neutronics, explosives, metallurgy, and nuclear physics—all disciplines essential to nuclear weapons development.

Despite the scale and effectiveness of these operations, Iran still maintains significant stockpiles of enriched nuclear material. The International Atomic Energy Agency estimates Iran possesses more than 200 kilograms of uranium enriched to 60% at Esfahan—potentially enough for approximately five nuclear weapons if further enriched.

President Donald Trump stated on April 17 that the US would collaborate with Iran to recover “nuclear dust”—enriched uranium—from strike sites, indicating that both countries would deploy heavy machinery for removal operations. However, Iranian Foreign Minister Seyed Abbas Araghchi contradicted this, claiming the material remains “under the rubble” of previous strikes and that Tehran has no plans to recover it.

Security analysts remain cautious about drawing definitive conclusions regarding the lasting impact of these operations. “It is always possible that Iran has additional sites that were not known to Israel and the US,” Lamson warned.

“We will have to wait to see how much these operations translate into a lasting strategic impact on Iran’s ability to produce nuclear weapons,” he added, noting the difficulty in assessing the actual impact on Iran’s capabilities and intentions beyond the visible damage caused by the strikes.

The situation continues to develop as international monitors work to maintain oversight of Iran’s remaining nuclear facilities amid heightened regional tensions.