Obama has stalled, prevaricated, and dissembled to buy time for Iran. I think this reality has finally dawned on Israel. Israel is on its own.
Putin is doing all he can to help Iran get a bomb. He could stop it today, but he won’t. It’s another part of his scheme.
A major problem with a strike on Iran’s nuclear sites is unexpected: that the typical “Iranian on the street” *wants* nuclear weapons. So if their nuclear sites are destroyed, they will just build more, *no matter* who is in charge.
Iran was not very developed after World War II, and though the last Shah was in power and very pro-development, the popular Iranian international conscience missed out on the rise and fall of nuclear weapons culture.
So for modern Iranians, nuclear weapons are just seen as “big bombs”.
The way around this dilemma is very ugly. A nuclear accident, or facsimile thereof. Thousands of Iranians need to die horrible deaths so that hundreds of thousands won’t have to. As a people they must learn the horror of nuclear weapons, so as a people they turn against it.
Many years ago, this could have been done harmlessly, by broadcasting “nuclear TV” into Iran. Showing them the horror of nuclear war. But it is now too late to do that.
They must now see a nuclear accident with their own eyes. Radiation burns, poisoning, sickness, and death.
It's safe to say that if Israel had the means of carrying out a conventional strike offering a probability of success they would have done so long ago.