Highly enriched uranium (HEU) — material concentrated to weapons‑usable levels — is central to the possible spread of nuclear weapons in the Iran conflict. Since strikes began last June, international inspectors have not been able to verify Iran’s holdings. Ongoing U.S. and Israeli operations and the broader war have complicated efforts to locate, secure, or account for remaining HEU. Washington essentially faces two pathways: negotiate Iran’s cooperation to package and remove the material, or attempt a forcible seizure — each option carries large operational, political, and verification challenges.
There is precedent for a successful removal. Project Sapphire, a 1994 U.S. operation in Kazakhstan, recovered roughly 600 kilograms of 90 percent HEU. Diplomacy and trust‑building created the political opening: U.S. officers spent months securing agreement from Kazakh authorities, aided by informal relationship‑building. The covert transport used a small specialist team and strategic airlift to move HEU in specially built, crash‑resistant containers to DOE facilities in the United States. Every kilogram was accounted for; the operation became a template for later NNSA efforts that have removed significant quantities of HEU from other countries.
But Iran presents a far tougher problem than Kazakhstan did. Intelligence and satellite imagery indicate a number of sites — including Isfahan and a site under Pickax Mountain — with hardened, subterranean storage: tunnel entrances, blocked approaches, heavy earthworks, and dispersed facilities. Analysts describe scuba‑tank‑sized canisters of HEU stored deep in tunnels and caverns that bunker‑busting munitions may not reliably reach. If large portions of the inventory are underground or spread across fortified sites, airstrikes cannot be relied upon to eliminate the material or the human expertise needed to rebuild a program.
Verification is as important as physical removal. Experts like Dr. Matthew Bunn emphasize that inspections do more than find material — they provide transparent accounting, continuous monitoring, and international confirmation that nothing remains. Without inspectors on the ground, claims that a program has been destroyed or that all HEU was destroyed are inherently uncertain: remaining material and retained knowledge can enable reconstruction. The target outcome is clear: no HEU and sustained, intrusive monitoring — but war and diplomatic rupture make getting to that outcome far harder.
A kinetic recovery would be dangerous and complex. Former special operations leaders outline what such a mission would demand: large forces to establish and defend perimeters, special forces trained in subterranean operations, engineering teams to clear obstacles and create landing zones, and logistics to package and transport radiological material securely. Forces would operate under the threat of missiles, drones, and irregular forces; casualties would be a likely, and politically consequential, possibility. Senior military figures say the United States has the capability to attempt such an operation, but it would probably require occupying and holding terrain while technical teams spend days or weeks excavating, packaging, and moving HEU — all under hostile conditions.
The safer route is negotiated removal, but it depends on Iranian consent and robust verification provisions. NNSA and DOE teams have led many international recoveries and stress that past removals required the host country’s cooperation. Practical steps in a cooperative transfer are well established: locate and inventory all HEU, place the material in certified crash‑resistant drums, secure overland and air transport, and move the consignments to secure facilities for storage or down‑blending. That effort would involve NNSA technical teams, DOE logistical support, and military security assets, just as Project Sapphire combined technical packaging with strategic airlift and cover operations.
Political and technical obstacles are substantial. Tehran has publicly rejected handing over HEU and has used rhetoric promising to reclaim any removed material, raising public and diplomatic risks. Even where strikes have damaged facilities, experts caution that radiological material and technical knowhow often survive attacks. Before the war, UN and IAEA assessments suggested Iran could have held hundreds of kilograms of 60 percent HEU — enrichment at those levels requires far less time and feedstock to reach weapons‑grade than starting from low‑enriched uranium, making such stockpiles particularly concerning.
Any deal must contain rigorous, independent verification. Specialists stress that international monitors, continual oversight, and technical safeguards are essential to ensure every gram is accounted for and that covert reconstitution is prevented. A unilateral raid, even if it seizes material, would not by itself provide the same level of international confidence unless followed by transparent accounting and third‑party verification — outcomes unlikely after a forcible operation.
Operational specifics further complicate a forcible recovery. Sites reported to house HEU are sometimes deep under mountains or in elaborate tunnel systems where munitions may not reach storage canisters. Excavating in such environments — especially while under fire — is slow, hazardous, and requires specialized equipment and DOE/NNSA technical expertise to package radiological material safely. Even if security forces control a site, safe handling and transport of HEU is a delicate, time‑consuming process.
In short, removing Iran’s HEU is technically possible but politically and operationally arduous. Project Sapphire demonstrates that diplomacy and cooperation make recovery far safer and more verifiable; without Tehran’s consent a recovery mission would be high‑risk, likely costly in lives and escalation potential, and would still leave difficult verification questions. The most durable path identified by experts is a negotiated transfer of material combined with sustained international monitoring and transparency to prevent the covert regeneration of a weapons capability.