Isaac Chotiner interviewed James M. Acton, the chair and co-director of the Nuclear Policy Program at the Carnegie Endowment for International Peace:

One point that opponents of the Obama deal have made is that Iran could have been using hidden sites to enrich uranium beyond what was allowed. But you have argued that that isn’t actually a case for military action. Why?

One of the big challenges with all I.A.E.A. [International Atomic Energy Agency] inspections everywhere is, Does the I.A.E.A. know where everything is? And there was always some risk with the J.C.P.O.A. [Joint Comprehensive Plan of Action] that Iran would have a secret facility or more than one secret facility in which it might be violating the deal. The existence of a secret facility in and of itself would be a violation of its I.A.E.A. obligations, and the J.C.P.O.A. contained a whole bunch of provisions designed to make it easier for inspectors to try to locate a clandestine facility.

One of the big criticisms of the J.C.P.O.A. was that these provisions were inadequate. But my argument is that there’s actually a bigger problem with military action, because if Iran has secret facilities that we don’t know about, then we can’t try to bomb and destroy them. And the effect of bombing and destroying will probably harden Iran’s resolve to make the political decision to build a nuclear weapon, potentially using those clandestine facilities that we don’t know about. Moreover, if Iran kicks out inspectors, as I think is pretty likely now, then one of the key ways we had to try to find clandestine facilities has evaporated. So, if you’re worried about clandestine facilities, my view is that bombing actually has made the problem worse than it would have been under a diplomatic arrangement.

You talked about the “political decision” to make a nuclear weapon. Iran has said that its nuclear program is peaceful. Both the United States and Israel under different governments have seemed very skeptical of that. Are you implying, when you talk about a political decision being made in the future, that that decision hasn’t been made?

I would distinguish between two things here. The first is Iran wanting the ability to build a nuclear weapon on short notice, and the second is Iran having made the political decision to actually go ahead and build the bomb.

So you are saying that you think they want the first one? It’s not simply a peaceful nuclear program, but that doesn’t mean that they were on the verge of taking the final step?

I think they’ve always wanted the capability to build a bomb on short notice. They’ve dialed up and down that program over the years. To build a nuclear bomb, you really need to do two things. Firstly, you need sufficient fissile material, meaning highly enriched uranium or plutonium. And, secondly, you need to know how to turn that material into an actual, usable, deliverable nuclear device. That is called weaponization. And they stopped their weaponization activities, according to U.S. intelligence, in 2003. That’s something the U.S. has said publicly and repeatedly. Tulsi Gabbard said that in testimony back in March. But I do believe that one of the reasons why they were continuing with enrichment was to maintain this capability to build a nuclear weapon on short notice. In that sense, even though they stopped weaponization activities in 2003, I don’t think the Iranian program has ever been purely peaceful.

Now, one of the things that [Benjamin] Netanyahu came out and implied in justifying the Israeli attack just over a week ago now was that Iran had actually started to build a nuclear weapon. But we have had a lot of intelligence leaks from the U.S. that disagree with that conclusion. And part of my concern now is that if the U.S. was right, if Iran hadn’t actually made the political decision to build a bomb, these attacks are going to lead it to make that decision. [Continue reading…]

The New York Times reports:

A day after President Trump declared that Iran’s nuclear program had been “completely and totally obliterated” by American bunker-busting bombs and a barrage of missiles, the actual state of the program seemed far more murky, with senior officials conceding they did not know the whereabouts of Iran’s stockpile of near-bomb-grade uranium.

“We are going to work in the coming weeks to ensure that we do something with that fuel and that’s one of the things that we’re going to have conversations with the Iranians about,” Vice President JD Vance told ABC’s “This Week” on Sunday, referring to a batch of uranium sufficient to make nine or ten atomic weapons. Nonetheless, he contended that the country’s potential to build a weapon had been set back substantially because it no longer had the equipment to turn that fuel into operative weapons.

In a briefing for reporters on Sunday, Defense Secretary Pete Hegseth and the new chairman of the Joint Chiefs of staff, Dan Caine, avoided Mr. Trump’s maximalist claims of success. They said an initial battle-damage assessment of all three sites struck by Air Force B-2 bombers and Navy Tomahawk missiles showed “severe damage and destruction.”

Satellite photographs of the primary target, the Fordo uranium enrichment plant that Iran built under a mountain, showed several holes where a dozen 30,000-pound Massive Ordnance Penetrators — one of the largest conventional bombs in the U.S. arsenal — punched deep holes in the rock. The Israeli military’s initial analysis concluded that the site, the target of American and Israeli military planners for more than 26 years, sustained serious damage from the strike but had not been completely destroyed.

But there was also evidence, according to two Israeli officials with knowledge of the intelligence, that Iran had moved equipment and uranium from the site in recent days. And there was growing evidence that the Iranians, attuned to Mr. Trump’s repeated threats to take military action, had removed 400 kilograms, or roughly 880 pounds, of uranium enriched to 60 percent purity. That is just below the 90 percent that is usually used in nuclear weapons.

Rafael Mariano Grossi, the director of general of the International Atomic Energy Agency, said by text that the fuel had last been seen by his teams of United Nations inspectors about a week before Israel began its attacks on Iran. But he said on CNN that “Iran has made no secret that they have protected this material.”

Asked by text later in the day whether he meant that the fuel stockpile — which is stored in special casks small enough to fit in the trunks of about 10 cars — had been moved, he replied, “I do.”