A high-ranking official confided to me that after this meeting Rouhani issued a general circular asking all Iranian departments and agencies, civilian and military, to report in detail about their past and ongoing nuclear activities. The official explained to me that the main difficulty Rouhani and his team were encountering was learning exactly what was happening in a system as secretive as Iran’s.

A few weeks after, I heard from another official, a close friend of Rouhani: “The Rouhani team is having a hard time ... People resist their instructions ... But they will prevail.” He went on to complain how difficult it was to convince researchers to abruptly terminate projects they had been conducting for years.

I told him of a similar case in Europe when a country had to implement the freshly signed Chemical Weapons Convention. The researchers were given enough time and funds to archive all the data they had collected in order to protect their achievements for the future. A while later, my interlocutor happily reported: “I conveyed your message ... It worked!”

My conviction that these officials were talking about the weaponization program was reinforced when the November 2011 I.A.E.A. report about the termination of that program noted that “staff remained in place to record and document the achievements of their respective projects.”

Of course, closing down a program run by the powerful Revolutionary Guards required the concurrence of the Supreme Leader, Ayatollah Ali Khamenei. There were two strong reasons for such a move:

First, by the end of 2003, Iran’s arch enemy, Saddam Hussein, had been eliminated by the United States, and it had been confirmed that the Iraqi clandestine nuclear program was stopped after Saddam’s defeat in 1991. It was the Iraqi program that had driven the Iranians to launch a similar endeavor in the 1980s, when they were fighting Iraq in the “War of Sacred Defense.” So the main motive behind Iran’s need for a bomb was gone.