The Battle for Isfahan’s Uranium Is About to Begin |
On April 8, 2026, one day after President Trump announced a ceasefire with Iran, Prime Minister Benjamin Netanyahu delivered a televised statement that left no room for ambiguity. “The enriched material that still remains will leave Iran,” he said. “It will leave either by agreement or through a renewal of the fighting.” He added that Israel and the United States “see eye to eye on this issue.” Hours later, Defense Secretary Pete Hegseth reinforced the message from the Pentagon: “We know exactly what they have, and they know that, and they will either give it to us voluntarily, or if we have to do something else ourselves, like we did in Midnight Hammer, we reserve that opportunity.” Secretary of State Marco Rubio, asked at a congressional briefing whether Iran’s enriched uranium would be secured, was blunter: “People are going to have to go and get it.”
That promise remains unfulfilled. The Islamabad talks collapsed on April 12 without a deal. Iran refuses to terminate its nuclear program, refuses to relinquish its uranium, and refuses to reopen the Strait of Hormuz without conditions. The ceasefire expires in days. The diplomacy is dead. What Netanyahu described is not a hypothetical. It is the next phase of the war.
The uranium is in Isfahan
I wrote those exact words two weeks ago in these pages, outlining five criteria that pointed to the Isfahan nuclear complex as the primary repository for Iran’s 441 kilograms of highly enriched uranium. The evidence has only grown stronger since.
The Bulletin of the Atomic Scientists, working with the French newspaper Le Monde, analyzed a satellite image from June 9, 2025, three days before Israel attacked and thirteen days before Midnight Hammer. The image shows a flatbed truck loaded with 18 blue containers positioned at the south tunnel entrance of Isfahan’s underground complex. The Bulletin’s analysis concluded that Iran may have transferred a significant quantity of highly enriched uranium, possibly all of its inventory, to Isfahan on that date. IAEA Director General Rafael Grossi subsequently confirmed that Isfahan held “a bit more than 200 kilograms, maybe a little bit more than that” of 60% enriched uranium as of the last inspection, with additional quantities at Natanz and possibly Fordow.
The Bulletin’s technical analysis noted that the truck’s capacity was in the same order of magnitude as the full 441 kilograms of 60% material reported by the IAEA. If correct, the enrichment vaults at Natanz and Fordow may have been largely empty when the bombs fell. Isfahan was not a secondary storage site. It was the vault.
The barricades tell the story
On April 9, 2026, satellite imagery analyzed by the Institute for Science and International Security revealed that Iran had installed makeshift roadblocks outside all three tunnel entrances to the Isfahan underground complex. At the southern entrance: a two-meter-wide dirt embankment and a second barrier of unidentified material. At the middle entrance: a completed dirt pile and another under construction. At the northern entrance: additional barriers including possible fencing and a chicane structure.
The Institute assessed that the barriers are “apparently intended to further limit traffic towards the tunnel complex, and to add complexity to any ground operation that seeks to enter it and seize the enriched uranium stored there.”
The question answers itself. You do not fortify the entrance to a tomb. You fortify the entrance to a vault. If the uranium were truly inaccessible, buried beyond anyone’s reach, there would be nothing to defend. The barricades are not a precaution. They are an admission.
Someone is watching from inside
For any of this to converge into an operation, someone has to know where the uranium is. Not approximately. Precisely.
The New York Times reported that U.S. intelligence agencies are constantly surveilling the Isfahan facility and believe they will know of any Iranian attempts to relocate the enriched uranium. U.S. Director of National Intelligence Tulsi Gabbard told Congress on March 19 that the intelligence community has “high confidence” in the location of the stockpile. Trump himself said the material is “under intense satellite surveillance and control.”
But satellites alone cannot see inside tunnels. The confidence has to come from somewhere else. Human intelligence. Someone on the inside who knows what the cameras cannot show.
This is also why Iran cannot risk moving the uranium. A truck on an Iranian highway at night is visible to every surveillance asset in the coalition’s arsenal. The moment the material leaves the relative protection of the tunnel complex, it becomes exposed on open terrain. Iran is trapped by its own geography. The uranium is safest where it is. But where it is, is exactly where they are coming.
The uranium is not buried
The official narrative, repeated by both Washington and Tehran, holds that the enriched uranium is buried under rubble and effectively inaccessible. This narrative is convenient for everyone. For Trump, it justifies not having extracted it yet. For Iran, it reduces the urgency of a military operation.
But the evidence says otherwise.
During Operation Midnight Hammer in June 2025, Fordow received twelve 30,000-pound GBU-57 bunker busters dropped by B-2 bombers. Natanz received two more. Isfahan received Tomahawk cruise missiles launched from a submarine. The Tomahawks struck surface infrastructure. The tunnel complex at Isfahan, built into a hillside, was not penetrated by these strikes. The Bulletin of the Atomic Scientists assessed with reasonable confidence that the United States chose to bury the material by targeting surrounding infrastructure to seal off tunnels and access routes, rather than attempting to destroy the uranium directly.
More importantly, satellite imagery from June 20, two days before the American attack, shows the Iranians themselves backfilling the tunnel entrances with soil. Iran sealed its own tunnels before the bombs fell. What Iran sealed, Iran can unseal.
And the proof that they have: Iranian Foreign Minister Abbas Araghchi offered in February to “down-blend” the enriched uranium in exchange for sanctions relief, effectively acknowledging that the material exists in a state and location that Iran can control. CNN reported that the Iranians had been working for months after the June 2025 strikes to clear rubble and access the underground tunnels. U.S. intelligence determined that there is now a “very narrow access point” through which the uranium could potentially be retrieved.
You do not offer to dilute what you cannot reach. You do not build barricades around what no one can enter. Isfahan is not a mausoleum. It is a guarded vault. And Iran has the key.
This changes the nature of the operation entirely. If the tunnels are already accessible, the extraction force does not need weeks of excavation with heavy equipment. It needs to reach the tunnel entrances, clear the barricades, enter the complex, and secure the canisters. The challenge is not engineering. It is combat.
What the MC-130s revealed
On April 5, 2026, during the rescue of a weapons systems officer from a downed F-15E, the United States established an improvised forward operating base on a remote agricultural airstrip approximately 400 kilometers inside Iranian territory, near Isfahan. The operation involved 155 aircraft, more than 100 operators from Delta Force, and two MC-130J Commando II special operations transports that became stuck in wet sand and had to be destroyed on the ground to prevent capture.
Iran’s foreign ministry spokesperson was quick to suggest that the operation may have been “a deception operation to steal enriched uranium.” The official American account maintains it was a pilot rescue. Both things can be true at once. Whether the mission was a rehearsal or an improvisation born of opportunity, it tested exactly the capabilities that a uranium extraction would require: penetration deep into Iranian territory, establishment of a forward airstrip, deployment and extraction of special operations forces, and close air support against approaching Iranian ground forces.
A former special operations officer noted that for a sustained ground mission to retrieve Iran’s enriched uranium, setting up forward arming and refueling points would be essential, and the Isfahan rescue demonstrated both the feasibility and the cost. Marines conducted FARP construction exercises in the California desert on April 1, days before the operation in Iran.
But the rescue also revealed the limits. Two MC-130J transport aircraft destroyed. An A-10 shot down providing close air support. The Iranian Army announced that four of its officers, including Brigadier General Masoud Zare, commander of the Army Air Defense College, were killed by a U.S. airstrike in Mahyar, Isfahan, while approaching the rescue site. And that was for one pilot. A uranium extraction would be orders of magnitude larger. Which brings us to the central military question.
What the operation really requires
The Washington Post reported that Trump personally requested a plan for the extraction and was briefed on it in late March. The original plan assumes the uranium is buried and involves flying in heavy excavation equipment, constructing a temporary runway, and deploying up to a thousand troops for weeks.
But if the tunnels are already accessible, the timeline and the force structure change. The operation shifts from a prolonged excavation under fire to a forcible entry through defended tunnel entrances. It is still massive. It still requires air superiority, a secure perimeter, specialized nuclear handling teams in hazmat suits, and aircraft to extract the material. But the weeks of digging that dominated every public estimate may not apply.
Even so, the details are sobering. The canisters holding Iran’s enriched uranium each weigh about 50 kilograms and number between 26 and 52. The material is uranium hexafluoride, which reacts violently with moisture to produce hydrofluoric acid. The canisters must be kept separated during transport to prevent a criticality event. Demolition experts would need to search for booby traps. And CBS News reported that Iran has likely mixed hundreds of decoy canisters among the real ones.
Isfahan is more than 480 kilometers inland from the nearest American naval assets. The Iranian air base at Badr sits just 10 kilometers from the nuclear complex. Hundreds of U.S. special operations forces have already arrived at bases across the Middle East. The 82nd Airborne, Rangers, and JSOC units are all capable of conducting the type of operation Isfahan would demand.
Iran will never surrender the uranium
Iran’s 10-point peace proposal demands the right to continue enriching uranium. Mohammad Eslami, head of Iran’s Atomic Energy Organization, said that any attempt to limit enrichment would fail. The Islamabad talks ended with Iran’s chief negotiator blaming the United States for their collapse.
This is not a negotiating position. It is an existential one. Iran spent four years accumulating those 441 kilograms. It required tens of thousands of centrifuges, billions of dollars, and decades of confrontation with the West. That stockpile is Iran’s insurance policy against regime change. They will not hand it over in a conference room in Islamabad.
They will fight for it. And they will fight until the end.
Here is the paradox that seals Isfahan’s fate. Every battalion of the IRGC stationed around the tunnel complex, every barricade erected at the entrances, every checkpoint and roadblock visible on satellite imagery, is simultaneously a defensive position and a target. Iran’s air defenses have been functionally destroyed over six weeks of war. Every concentration of forces around Isfahan is a coordinate that feeds directly into the coalition’s targeting system.
The rescue operation on April 5 demonstrated this in miniature. U.S. attack aircraft bombed approaching Iranian convoys to keep them away from the operating area. A brigadier general and three officers were killed in a single airstrike while responding to a rescue mission. That was the cost of approaching a site defended by a fraction of available coalition air power. The cost of approaching a uranium extraction site, defended by its full weight, would be catastrophic for the defenders.
The more Iran fortifies Isfahan, the more it reveals. The more forces it concentrates, the more vulnerable those forces become. The fortress becomes the trap.
The battle for Isfahan will have a winner. It will be violent, it will involve casualties on both sides, and it will end only when every canister has been accounted for or the decision is made that the cost of continuing exceeds the value of what remains underground.
Isfahan is where Iran’s nuclear ambitions were stored. Isfahan is where they will be contested. The only question that remains is whether the men who go in will find the uranium still waiting for them, or whether they will arrive to discover that the vault was emptied while the world debated the terms of a peace that neither side believed in.