It's become an annual event on the diplomatic calendar: The United States and its allies press Iran to stop enriching uranium, Iran says no, Israel warns that its patience is running out, and the United States persuades Israel to stay its hand.
That's how the crisis has unfolded over the last two years. But there are several reasons to believe that 2013's crisis will be different, and that Tehran will either agree to limit its nuclear program, or Israel and the United States will move toward military action.
For one thing, President Obama's reelection gives him a freer hand to make a deal or to consider military action if a deal can't be reached. Israeli Prime Minister Benjamin Netanyahu is about to get reelected too, and he will head an even more hawkish government. And one more element has changed: Over the past year, Obama has hardened his warnings that the United States will not allow Iran to go nuclear, even if that requires military action.
"A nuclear-armed Iran is not a challenge that can be contained," he told the U.N. General Assembly in September. "The United States will do what we must to prevent Iran from obtaining a nuclear weapon."
The president still has doubters in both the United States and Israel. When Obama hardened his position against Iran, they note, it was an election year, and he needed to sound tough to stave off Israeli military action and placate pro-Israel voters. Now that he's been reelected, his true antiwar beliefs will resurface, they predict. As proof, they say, there's his nomination of former Sen. Chuck Hagel as secretary of Defense — a Republican who has been one of his party's most vocal skeptics about the wisdom of military action against Iran.
"Once you start [an attack on Iran] … you'd better be prepared to find 100,000 troops, because it may take that," Hagel warned in 2010.
In a 2008 book, Hagel suggested that the United States might be able to live with a nuclear-armed Iran, just as it learned to live with a nuclear-armed Soviet Union.
"Of course we would like to see Iran free of nuclear weapons," he wrote then. "But the genie of nuclear armaments is already out of the bottle, no matter what Iran does."
But that was the old Hagel, before he was nominated for secretary of Defense. Last week, as he prepared for his confirmation hearings, Hagel took pains to reassure senators that he is falling fully in line with Obama's tougher position on Iran.
"He strongly supports the president's position on Iran," one official told me after speaking with Hagel at the Pentagon. "He agrees that military action should be on the table."
In a conversation with Dennis Ross, Obama's former advisor on Iran, Hagel went a step further into the hawkish camp.
"He was very clear that he believes we can't live with an Iran that has nuclear-weapons capability," Ross told me.
Is that the Washington equivalent of a deathbed conversion — a sudden change of view on the eve of confirmation hearings? Maybe. But it's also a sign that Obama isn't softening his stance on Iran for his second term, and that embracing Obama's view was a price of Hagel's nomination.
"The president has been unequivocal about his determination to prevent Iran from getting a nuclear weapon," White House spokesman Tommy Vietor told me. "Everyone who works for him will be charged with executing that policy."
Indeed, the White House hopes to turn Hagel's confirmation hearing into an opportunity to reinforce its hard line. Obama's first two secretaries of Defense, Robert M. Gates and Leon E. Panetta, both warned publicly against the costs of going to war with Iran. Hagel is likely to make it clear that, despite the costs, he accepts that the threat of war is necessary.
"We still have a challenge to convince the Iranians that we're quite serious about the use of force," Ross said. "In the first term, the administration didn't always speak with one voice on this issue. So what Hagel says can make a difference…. It could affect Iranian perceptions and Israeli perceptions."
The point of all this saber-rattling isn't to start a war, of course; it's to increase the pressure on Iran to agree to limits on its nuclear program.
"For diplomacy to have a chance of success, the Iranians need to understand that if diplomacy fails, force is going to be the result," Ross said.
And even if diplomacy fails, Obama could attack Iran's nuclear program with covert action, sabotage or limited airstrikes before resorting to full-scale war.
But anyone who expected Chuck Hagel to become a strong force for restraint in Obama's second term may be disappointed. Instead, we are likely to have an antiwar president and an antiwar secretary of Defense, both bent on convincing Iran that they are willing to go to war.