The fate of the war between Iran and America hinges on three letters: HEU — highly enriched uranium — a critical ingredient for nuclear weapons. Iran is believed to hold enough HEU to eventually make about ten atomic bombs, but international inspectors have not been allowed to verify its stockpile since last June, after U.S. and Israeli strikes on three nuclear sites.
President Trump has said the U.S. will take whatever HEU remains, either by force or by negotiating with Iran to allow experts to secure the material and bring it to the United States. That option has a precedent: Project Sapphire, a covert 1994 mission to remove weapons-grade uranium from Kazakhstan after the Soviet Union’s collapse — a possible blueprint for removing HEU from Iran.
Andrew Weber, then a young foreign service officer in Kazakhstan, discovered a cache of uranium enriched to 90% U-235 at a factory. Uranium at that level is weapons-ready. The revelation reached President Bill Clinton, and the U.S. agreed to take the stockpile to prevent other states from acquiring it. Webber described building trust with the factory director through diplomacy and even a moose hunting trip; the director ultimately handed a note revealing the cache.
Project Sapphire deployed three C-5 Galaxy cargo planes and a 31-person team from the Departments of Defense and Energy. Teams brought 450 heavy-duty drums designed to survive a crash and, under cover of a humanitarian mission, quietly packaged more than 1,300 pounds of bomb-grade uranium. The HEU was loaded onto Soviet-era trucks and moved through hazardous winter roads to the planes, then flown to Oak Ridge, Tennessee, for safekeeping. The operation took about six weeks and remained secret until completed.
Would the same mission work in Iran? Experts say it would be far more difficult. Andrew Weber noted that in Iran, a unilateral insertion of a U.S. team would be extremely risky. The Isfahan nuclear facility, deep under a mountain in Iran’s desert, is believed to store most of Iran’s HEU in scuba-tank-sized containers inside deep tunnels, potentially beyond the reach of bunker-busting bombs. Satellite images show tunnel entrances blocked with dirt and roadblocks, suggesting Tehran is preparing for possible raids.
Dr. Matthew Bunn, a former White House nuclear adviser at Harvard’s Belfer Center, cautioned that surface satellite imagery cannot reveal activities inside buildings or deep underground facilities. He said strikes and war have set back Iran’s capabilities but have not eliminated them; you cannot “bomb away” knowledge. U.N. inspectors estimate Iran may have close to 1,000 pounds of uranium enriched to about 60% — nearly weapons-grade and, if further enriched, enough for roughly ten nuclear bombs.
Another suspected site, Pickaxe Mountain, shows satellite evidence of a major underground facility carved into solid rock. Military options to reach such deep stockpiles face severe challenges. Scott Roecker, a former senior official at the National Nuclear Security Administration (NNSA), which has overseen previous HEU removals, emphasized that past removals depended on agreement and cooperation with host countries. The NNSA has, to date, removed over 16,000 pounds of HEU worldwide, but Roecker has never seen a removal done without a willing partner.
If an operation in Iran were attempted unilaterally, U.S. Special Forces would need to secure a facility, possibly requiring thousands of troops to hold a broad perimeter while experts excavated materials housed in deep tunnels. Vice Admiral Robert Harward, retired Navy SEAL and former deputy director of U.S. Central Command, said such an operation would be high-risk and likely take many weeks with a large footprint, drawing on all military branches. Troops might have to build infrastructure — clear rubble, construct landing strips or runways, and bring in heavy equipment — as U.S. forces have done in past conflicts.
Harward warned that Iranian retaliatory capabilities — drones, kinetic systems, and remaining missile inventories — would pose substantial threats to forces on the ground, and any operation should plan for casualties. He believes seizing HEU would be worth the risk, but acknowledged the inherent dangers.
Project Sapphire’s success relied on secrecy, diplomacy, and a permissive host. The Kazakh government cooperated, enabling U.S. teams to package and remove the material without open conflict. By contrast, Iranian authorities have denied that they would hand over HEU. President Trump claimed Iran agreed to “hand over its stockpile,” while Iran insisted its HEU would not go anywhere. Roecker noted that removals led by the NNSA require agreement in place with the host country.
Experts argue that the most viable path to secure Iran’s HEU is negotiation and strict verification. Matthew Bunn stressed that any durable solution must eliminate highly enriched uranium from Iran and establish in-depth international monitoring. Trust alone is insufficient given Iran’s history: Bunn said Iran has lied about its nuclear weapons efforts for decades, repeatedly denying weaponization until inspections uncovered incriminating evidence. The built-up distrust following war and the U.S. pulling out of talks complicates prospects for cooperation.
If negotiation fails, options narrow to high-risk military operations or continued efforts to contain and monitor Iran’s program from afar. Military seizure of HEU would require a massive, sustained operation: secure perimeters, heavy logistics, specialized containment and transport capabilities, protection from asymmetric threats, and political will to accept potential casualties and international fallout. Even then, deep underground storage and dispersed facilities could limit the effectiveness of kinetic strikes and complicate recovery of material.
In short, removing Iran’s HEU would be far more complex than Project Sapphire. Success would most likely require Iranian consent and international verification mechanisms. Without cooperation, any attempt to seize HEU would be dangerous, uncertain, and potentially costly in lives and regional stability. Experts warn that, absent a negotiated agreement with robust monitoring to eliminate and verify the absence of HEU, the international community will face a persistent challenge in preventing proliferation.