Attack. If President Obama and his war cabinet huddle before the Moscow meetings, and conclude Iran is blowing smoke, they could order an attack. Or, they could look the other way and let Tel Aviv launch its own strike.
But either of those options seems unlikely, experts say.
"The last thing the president wants is an attack before the election in November—especially an Israeli attack," says Mark Dubowitz, executive director of the Foundation for Defense of Democracies.
Still, it might be possible to take out Iranian facilities where the obstinate regime is believed to be producing nuclear centrifuges, Dubowitz says.
"The centrifuge-production facilities are the key choke points for the broader program," Dubowitz says. "If Israelis know where they are and do bomb them, a strike like that could set the program back 10 years. And I think the Israelis have a pretty good idea where they are. Those facilities would be central to any military plan."