The targeted elimination of Iranian nuclear scientists through U.S.-Israeli military operations has sparked concerns about the potential consequences of a destabilized Iranian regime. Such instability could compromise the management of uranium reserves and facilitate the unauthorized spread of nuclear knowledge and materials.

Although Iran can eventually replace its personnel, experts highlight that restoring the lost specialized knowledge poses a greater challenge. Moreover, undisclosed locations within the country may harbor nuclear materials and expertise that could become susceptible to misuse.

According to Kelsey Davenport, who oversees nonproliferation policy at the Arms Control Association, “the threat of nuclear terrorism or illicit nuclear trade is currently minimal.”

“Non-state actors would encounter significant obstacles in obtaining enriched uranium, and it is improbable that they possess the necessary infrastructure to elevate it to weapons-grade status or transform it into the metallic form needed for a nuclear warhead,” she explained.

In Tehran, Iran, mourners congregate around the flag-draped coffins of Iranian generals, nuclear scientists, and their family members, victims of Israeli strikes, during a funeral ceremony on Saturday, June 28, 2025. (Vahid Salemi/AP)

“Nonetheless, if Iran’s current government collapses or if internal conflict leads to substantial turmoil, the likelihood of nuclear materials being stolen or redirected to undeclared sites increases,” Davenport added.

“There is also a risk that Iranian nuclear scientists may be willing to sell their expertise to states or non-state actors seeking nuclear weapons,” Davenport said in a new report.

Several senior figures in Iran’s nuclear and defense infrastructure have been killed over the past two years, coinciding with the campaign of U.S. and Israeli strikes on Iran’s nuclear facilities between 2025 and 2026.

Among them is Hossein Jabal Amelian, head of the Organization of Defensive Innovation and Research (SPND), who was killed in 2026 during Operation Rising Lion and Operation Epic Fury.

President Pezeshkian said Iran would rebuild the nuclear facilities targeted by the US, and make them stronger in 2025. (Iranian Presidency / Handout/Anadolu via Getty Images)

SPND is seen as the successor to Iran’s pre-2004 nuclear weapons program and plays a key role in new weaponization research.

Others killed in 2025 include Mohammad Mehdi Tehranchi, Akbar Motallebizadeh and Said Borji, all linked to weaponization work.

“The full impact of this campaign on Iran’s weaponization capabilities remains unclear,” Jim Lamson, a senior research associate at the Center for Nonproliferation Studies, told Fox News Digital.

“There will be replacements of the managers and scientists, but the impact on the killed officials’ experience and expertise will be hard to replace,” the former CIA analyst said.

“Many key scientists involved in suspected weaponization work were killed in 2025 and 2026.”

“Their successors may also fear being targeted in the future, whether by military strikes or assassination. That could affect their motivation and willingness to participate in any nuclear weapons program.”

Coffin during the funeral for Iranian nuclear scientist Mohammad Reza Sedighi Saber. (Alborz Irani/SOPA Images/LightRocket via Getty Images)

Lamson also said many of those targeted were embedded in sensitive areas of Iran’s nuclear work, including the fuel cycle and weaponization.

“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.

“The scientists also had expertise in weaponization — that is, in key aspects of the design and production of nuclear explosive devices,” Lamson added.

That said, U.S. and Israeli targeted strikes have also hit a network of sites tied to their work, creating extra obstacles for Iran’s program in the near term, he said.

“We have identified at least 11 weaponization-related sites that have been hit since 2024,” Lamson said.

“These include SPND headquarters, a newly identified site called Min-Zadayi in northeast Tehran, SPND’s Taleghan and Sanjarian explosives testing sites, the Defense Ministry’s Shahid Meisami complex in western Tehran and several research universities.”

These facilities were all involved in neutronics, explosives, metallurgy and nuclear physics — all tied to nuclear weapons development, he said.

Satellite imagery shows reinforcement efforts at Pickaxe Mountain site as Trump says Tehran pursuing nuclear weapon (Vantor/Reuters)

Despite the scale of the latest strikes, Iran retains enriched nuclear material, with President Donald Trump saying April 17 that the U.S. would work with Iran to recover “nuclear dust” — enriched uranium — from sites, adding that both countries would use heavy machinery to remove it.

The International Atomic Energy Agency also estimates Iran still holds more than 200 kilograms of uranium enriched to 60% at Esfahan—enough for roughly five weapons if further enriched.

Iranian Foreign Minister Seyed Abbas Araghchi also said it remains “under the rubble” of previous strikes and that Tehran has no plans to recover it.

“It is always possible that Iran has additional sites that were not known to Israel and the U.S.,” Lamson said.

“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.”

“It’s easier to identify the damage and death caused by the Israeli and U.S. strikes, and harder to assess their actual impact on Iran’s capabilities and intentions to produce a nuclear weapon,” Lamson clarified.