Iran has emerged from five weeks of punishing U.S. and Israeli bombing with most of the tools it needs to make a nuclear bomb intact, officials and experts say, giving its negotiators another lever for pressing Washington to make concessions.
While Iran has gained a powerful new point of economic leverage through its control of the Strait of Hormuz, the U.S. and Israel have long been focused on preventing Tehran from obtaining a nuclear weapon. Thwarting Iran’s nuclear ambitions was one of Washington’s top reasons for going to war.
U.S. and Israeli strikes destroyed labs and research facilities that they say Iran used for its nuclear weapons-related work. They also further damaged its enrichment program, taking out a site for making yellowcake—the raw material that can be turned into enriched uranium.
But Iran still likely has centrifuges and a site deep underground where it may be able to enrich uranium, experts say. Crucially, it held on to its stockpile of nearly 1,000 pounds of near weapons-grade uranium—half of it buried in caskets in a tunnel deep under its Isfahan nuclear site, according to the U.N. atomic agency.
“Iran is not going to trade those away easily. Its demands are going to be higher than they were” during talks in February for surrendering the material, said Eric Brewer, a former White House official who worked on Iran during Trump’s first administration.
White House press secretary Karoline Leavitt said Wednesday that Iran had indicated it was prepared to surrender its enriched uranium and that getting Tehran to do so was a priority for the U.S. She said ending uranium enrichment in Iran was a “red line” that Trump wasn’t going to back down from.
Much of the damage that has been done to Iran’s nuclear program occurred during the 12-day war last year. The U.S. dropped its Massive Ordnance Penetrator bombs on two uranium enrichment sites—Fordow and Natanz—and destroyed nuclear-related buildings at Isfahan with Tomahawk missiles.
During the recent five weeks of fighting, the U.S. focused on striking Iran’s missile stockpiles and launchers and other conventional military assets, which they said threatened to make it too costly to attack Iran’s nuclear program in the future. Israel, meanwhile, went after the nuclear program.
Israeli officials say they struck a range of sites where they believe that Iranian nuclear-weapons work was going on, including labs, a university, a facility outside Tehran and a building at the Parchin military site where Iran was conducting high-explosives tests. They also targeted Iranian nuclear scientists—as they did in last year’s war—although they haven’t said who or how many.
Yet, Iran likely still has most of what it would need to build a bomb, including centrifuges and its stockpiles of enriched uranium. The tunnels at Isfahan are also thought to house an enrichment site that Iran declared last June but that has never been inspected. The International Atomic Energy Agency says the site may not be operational. Iran also has a highly fortified tunnel complex in the so-called Pickaxe Mountain, near the Natanz facility, where it could potentially do nuclear work out of reach of even the most powerful U.S. weapons.
President Trump weighed a military operation to seize Iran’s stockpile of enriched uranium, The Wall Street Journal has reported. But the operation would have been complex and dangerous, potentially extending the timeline of the war.
Iran has previously refused to give up its uranium enrichment program. Iran claims its nuclear activities are for peaceful purposes. White House special envoy Steve Witkoff has said Tehran can demonstrate that by ending its domestic enrichment and accepting delivery of enriched uranium from abroad. Trump again in recent days demanded Iran accept zero enrichment.
The U.S.-Iran negotiations in February failed to reach an agreement on enrichment. Tehran offered to dilute the 60% highly enriched uranium to at most a 20% level, according to people involved in the talks. While it takes around a week to enrich 60% material to weapons grade, it takes a few weeks to enrich 20% to that level. Under the 2015 nuclear deal, Iran’s enriched uranium stockpile was capped at 3.67% for 15 years.
One senior official who has been involved in talks said that the key negotiations on the nuclear issues are unlikely to happen in the first stage of talks in Pakistan but will take center stage later. The initial talks may well focus largely on Iran’s control of the Strait of Hormuz and the price Tehran sets for relaxing its grip on the vital sea lane.
The key uncertainty about the attacks on Iran’s nuclear program since Feb. 28 is the extent of damage done to Iran’s ability to build a nuclear warhead. It takes experienced scientists to safely mold volatile fissile material into uranium metal for a warhead and to build in other crucial components.
Experts are almost certain that Iran has never built a warhead. It would be difficult for Iran to do it now without being detected, given the deep intelligence penetration Israel and the U.S. have gained over Iran’s nuclear work.
The biggest uncertainty is how much damage Israel has done to Iran’s ability to weaponize its nuclear program, but it may have been significant, said David Albright, a former weapons inspector who closely follows Iran’s nuclear program as the president of the Institute for Institute for Science and International Security.
If that is the case, it would weaken Iran’s leverage.
“On the weaponization side, the damage appears to be like punching holes, creating bottlenecks in the multitiered, lengthy process of making the nuclear weapons itself,” Albright said. “The damage appears to be significant.”
Write to Laurence Norman at laurence.norman@wsj.com