A whole series of American presidents have pledged to support Israel no matter what. American support includes their influence over NATO and the UN and any other American allies. Israel has cashed in those pledges over and over and over again and they plan to get a lot more milage out of them. Israelis are certain that, if they start a war with Iran, America would be FORCED to join the war. By making this attack before November, Israel plans to get rid of Iran and Obama all in one blow. It would be a terrible miscalculation on Israel's part if Obama did not perform as expected.
U.S., allies conduct 22 strikes against ISIS targets in Iraq, Syria (Reuters)
from the article: NATO official: Soon, Israel won’t have unanimous support for Iran strike