The whole Israeli/USA/ Iranian battle is not really open to rational analysis, for there are far too many variables. I wil add some more speculation.I suspect the Obama's number one priority is the establishment of some form of Palestinian self determination. If Israel goes it alone against Iran, Obama can quite nicely control the response to allow Israel to get enough of a bloody nose, and force concessions from the Israeli's, all behind those wonderfully posed smiles at joint press conferences. And he will be able to appear as Israel's saviour. Best not to underestimate the ability of the man. Bibi will over play his hand. Unfortunately he believes his own BS.
Palestinians report IDF airstrikes on Islamic Jihad targets in southern Gaza Strip (Haaretz)
from the article: Netanyahu's conspiracy to drag the U.S. to war