Iranian students carrying anti-US placards and portraits of the Islamic republic's supreme leader Ayatollah Ali Khamenei protest outside the Fordo Uranium Conversion Facility in Qom, in the north of the country, on November 19, 2013.(AFP/Getty)

Ayatollah Ali Khamenei, the Supreme Leader of Iran (whom we noted yesterday is supremely loaded even as sanctions lay waste to Iran’s economy), has his country’s final say in the nuclear negotiations with the P5+1 Group currently at work in Geneva. He also had the final say in which candidates Iranians could choose from in their presidential election earlier this year. It seems safe to say that whatever he says in Iran, goes.

So while the diplomats were hours away from resuming their good work to try and resolve a crisis that could drag Middle East further into war, Ayatollah Khamenei offered this kernel of goodwill to members of his military yesterday.

In an address to an assembly of tens of thousands of Basij militiamen, Khamenei declared that Israel was doomed to fail and characterized the “Zionist regime” as the “sinister, unclean rabid dog of the region.” He also said Israelis “cannot be called human beings.” Footage of the event showed the crowd shouting “Death to America” and “Death to Israel.”

France was among the first to respond, calling the remarks “unacceptable,” adding that the statement complicates the talks now underway in Geneva. The response was made by spokeswoman Najat Vallaud-Belkacem on behalf of French President François Hollande. The American reaction, however, came from a senior U.S. official, who was speaking on behalf of…him/herself…anonymously. Here’s what we got:

“Of course I don’t ever like it when people use rhetoric that in any way talks about the U.S. in ways that I find very uncomfortable and not warranted whatsoever,” the official told reporters assembled in Geneva to cover Iran nuclear talks this week.

So what gives? Well, this is the latest in a role reversal between the United States and France that has been on display for the past two weeks.

Then, French Foreign Minister Laurent Fabius publicly broke from the U.S. and other international powers and called the terms of the agreement being pursued with Tehran a “fool’s game.”

French officials said Wednesday that the tone and timing of Mr. Khamenei’s comments vindicated the skepticism Paris has displayed toward Iran. American officials, conversely, said they didn’t view the supreme leader’s words as necessarily undermining their pursuit of a deal aimed at preventing Iran from developing nuclear weapons.

If this speech was a way for Khamenei to project strength and defiance for the home crowd as the negotiations pick up again, he did it with gusto. More than a little too much gusto. As diplomats try to work through the puzzle of Iran, its intentions, and its capabilities, they should also consider another less complex puzzle: What does one do with a rabid dog?