I can't see open war with Iran at this point. For several reasons. Here are my top ones.
1. Already have a two to 2.5 front war going on in Iraq, Afghanistan, and limited ops in Pakistan.
2. Evidence of , "Cracks in the Wall", with the turnout of the voter fraud demonstrations we saw recently. It appears they don't have as much control as they would like. It would be easier to sit back and see if it crumbles from within.
3. There are rumors of a existing proxy war already being waged by the US and allies inside Iran any way.
Featured Article - WSJ.com
Proxy war could soon turn to direct conflict, analysts warn | World news | The Guardian
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4. Open war would alienate current diplomatic missions with other middle east allies.
And the list goes on. If I had to put my money on a horse here, it would be number three. I think this is has all the makings of the next, "Cold War", for the United States.
Again just my opinion.