After busting Iran’s bunker, US spies stumped by classic quantum riddle

(Originally published June 27 in “What in the World“) As U.S. intelligence officials slowly fall into line with Trump’s insistence that airstrikes obliterated Iran’s nuclear capabilities, a big mystery remains.

Where is Iran’s enriched, bomb-making uranium? Before the attacks, officials believed that Iran had roughly 408 kilograms of highly enriched uranium, produced since 2021, hidden away. One theory was that it was buried deep under a mountain at Iran’s Fordow Uranium Enrichment Plant, which American B-2 bombers hit with 12 GBU-57 Massive Ordnance Penetrators (MOPs) “bunker buster” bombs on June 21. Trump claimed the attack completely obliterated the site and presumably the enriched uranium stockpile along with it.

But as the dust settles over Fordow, U.S. officials aren’t so sure. While Trump and White House officials have stuck to the line that the stockpile was destroyed, some experts say it had long been assumed that, if faced with an attack like the one Israel launched June 13, Tehran would spirit its stockpile elsewhere to protect it. European intelligence suggests that it wasn’t at Fordow at the time of the airstrike.

But Trump and his officials insist the stockpile wasn’t moved. “Nothing was taken out of facility,” Trump posted on social media. “Would take too long, too dangerous, and very heavy and hard to move!” Not so, says the International Energy Agency. The IEA says that somehow that 408kg of uranium was in containers small enough to stuff into the trunk of a car. And vehicles were spotted moving something in or out of Isfahan in the days before the U.S. airstrike.

Defense Secretary Pete Hegseth said Thursday he was unaware of intelligence suggesting Iran had moved the stockpile. Iran’s foreign minister acknowledged Thursday only that the nuclear facilities had suffered “significant and serious damages,” but Iran’s supreme leader, Ayatollah Ali Khamenei, said in a video recording that the U.S. attacks “were unable to do anything important.” The head of the International Atomic Energy Agency, said on French radio Thursday that, after examining satellite images of Fordow, the site’s centrifuges for enriching uranium are “no longer operational”—meaning Iran wouldn’t be able to use them to add to its stockpile or replace it. But U.S. Vice President JD Vance said in an interview last Sunday that Washington was hoping to quiz Tehran about the fate of that stockpile.

Some believe the stockpile was at Fordow. Some think it was at Iran’s Natanz Nuclear Facility to the southeast, which U.S. B-2s hit with two bunker busters. Others think that it was even farther south at the Isfahan Nuclear Technology/Research Center, which was struck by U.S. submarine-launched Tomahawk missiles. Others think it had been spread around to various locations.

So now the quantum mechanics problem posed in 1935 by physicist Erwin Schrödinger comes into play. In a discussion with Alfred Einstein, Schrödinger used the analogy of a cat sealed in a box with a vial of poison to explain how a subatomic particle could occupy two states simultaneously. His thought experiment was a little complicated, but it boiled down to this: as long as we can’t see inside the box, the cat is both alive and at the same time dead.

It’s the same with Iran’s uranium stockpile. It may very well be buried in rubble deep underground (in which case it may have been not so much destroyed as turned into a delicate mining challenge). But until someone digs it up or spots it in the wheel well of an Iranian sedan, the U.S. and Israel have to assume that Trump is right, the stockpile has been destroyed, and at the same time that Trump is wrong, the stockpile remains hidden elsewhere alive and fissionable.

For the purposes of handling Iran’s nuclear threat, military planners have to assume that Iran’s nuclear program has only been set back a couple of months and that the threat remains only slightly less imminent than it was on June 12. Is this new form of superposition preferable to the status quo ante, in which we had a pretty good fix on where Iran’s stockpile was? You be the judge.

Speaking of radiation, a heat wave sweeping the U.S. this week set new high-temperature records at 282 locations, including New York City, which recorded its hottest day since 2012—37.2°C.