It’s most unlikely that the “special commodity” and the technical know-how surrounding it have anything to do with ballistic missiles; Rafsanjani expresses anxiety that the “special commodity” could be intercepted by the United States, but doesn’t share this worry about missile procurement. In a March 9, 1992, journal entry, the cleric gloats about the U.S. Navy having tracked a North Korean ship bound for Syria but not two ships destined for Iran. Two days later, when the “special commodity” is unloaded, he writes: “The Americans were really embarrassed.”

Odds are high that even today the Central Intelligence Agency doesn’t know what Rafsanjani got from Pyongyang, but it is safe to surmise that the North Koreans weren’t clandestinely building a peaceful nuclear reactor at Deir al-Zour . CIA Director John Brennan has often asserted that U.S. intelligence doesn’t believe that the clerical regime is on the verge of making atomic weapons, and he further claimed that Langley could detect any Iranian decision to sneak toward the bomb. But Washington hasn’t guessed correctly once since World War II about the timing of nuclear weaponization by foreign powers (the A-bombs of close allies Britain and France don’t count). Odds are good that North Korea helped to jump-start Iran’s nuclear-weapons program. If so, how long did this nefarious partnership continue?