The bad news is that, for the Iranians to give up such a high-profile trump card, they need to get something in return—a suspension of sanctions, a guarantee of security, something that’s tangible and valuable. Is there some deal—even hypothetically—that is, at once, worthwhile to the Iranians and acceptable to the Israelis? That’s the key question; it’s hard to envision such a thing.

In fact, if the Israelis really are intent on attacking the Iranian nuclear facilities, they’re likely to do so before this November’s American presidential elections. If they started an attack and needed U.S. firepower to help them complete the task, Barack Obama might open himself up to perilous political attacks—for being indecisive, weak, appeasing, anti-Israel, you name it—if he didn’t follow through. It could cost him the votes of crucial constituencies. If the Israelis tried to pressure the United States into joining an attack after the election, Obama would have (to borrow a phrase from another context) more flexibility. So, to the extent the Israeli leaders have decided to attack (and it’s not at all clear they have), they are probably thinking: much better sooner than later.

One thought worth considering is that the Iranians have probably contemplated this scenario as well. They certainly do worry about an Israeli attack, and for good reason. The fact that they’ve buried some of their facilities so deeply underground, at great cost, attests to this. If they think the Israelis are serious, maybe they will come up with a deal to avert a strike, at least for the next several months. The question, then, is whether their offer—whatever it is—seems authentic and sufficiently tempting for the Israelis to accept.