I don’t think so.
Given Iran’s behaviour, it would be a justified, mind you. But I don’t think so. Our military is too stretched and too invested in counter insurgency in Iraq and Afghanistan.
Also, if President Bush were planning operations against Iran, he would need permission from Congress - “authorization to use force” or, better yet, a declaration of war. The odds of getting those are less than none...
Bush could be thinking, what do I have to lose? He can’t get more unpopular. His legacy cannot be tarnished more by bombing Iran.