Israel is tiny, even if you include occupied Palestine as a part of the equation and Iran is huge - Israel would be wiped out long before Iran. If Israel attacks and that is the only way there will be a war - the Iranians are not so stupid - then world support, minus the US and a few toadying lackies will be for Iran which means the US will be prevented from doing too much damage to Iran. Not that it would matter since Israel would be finished anyway.
Woman wounded by stones thrown toward her car near Jerusalem (Haaretz)
from the article: The common cause of Netanyahu and Ahmadinejad