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New details are still leaking out about the diplomatic hoops diplomats were required to jump through in order to make the historic nuclear deal between the U.S. and Iran happen. In this chapter, all they had to do was return a stolen chalice.

According to this insane L.A. Times story, the U.S. was debating how best to acknowledge Hassan Rouhani's election as Iran's new president. The two countries were already knee-deep in secret, back-channel negotiations, but, on the surface, the relationship was cold as ever. One diplomat convinced the President's foreign policy team the best way to get in the country's good graces, is to return the 7th century, priceless Iranian chalice they've long wanted.

An art dealer illegally smuggled the chalice, looted from an Iranian cave, into the U.S. in 2003 to orchestrate a multi-million dollar sale. The State Department heard about his plan, confiscated the chalice, and it sat in a climate-controlled warehouse ever since. The diplomats knew Iran wanted it back.

Most importantly, retrieving the chalice earn Rouhani praise in Iran, endearing him to hardliners and building confidence among his people. So when both leaders were in New York for the U.N. General Assembly, the plan was set. Instructions were given to the diplomat who cares for the chalice explaining how to return it:

U.S. and Iranian diplomats can talk with one another on a short list of issues, such as helping the Iranians set up a bank account or get diplomatic license plates. The U.S. diplomat called the Iranian contact for such matters and said he had something to deliver before Rouhani left. The Iranian agreed to meet. Quickly, the diplomat took a photo of the griffin and printed a card explaining its history and why it was in U.S. hands. The Iranian contact might not recognize the object, he worried. Thinking a cardboard box was no way to present a precious object, he bought a white gift bag at Hallmark, choosing that color so as not to imply it was a gift. "Plain white gift bags are actually kind of hard to find," he said in a recent interview.

The Iranians love the gift, and accepted the gracious offer to build relations. Two days later, Rouhani and Obama were talking on the phone like it was no big deal, as if the two countries speak more often than once every three decades.

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