[Bush would love to take out the Iranian regime. The thing stopping him is the international left and our home grown Dems and their relentless defeatism and isolationism.]
My take is that it is the isolationist FReeper contingent that is stopping him.
Conservative Europeans are with us on this, but this time around we have to get creative. We must clearly have tens of thousands of Muslim fighters seen invading. Even if they are invading sectors that are not important (only the oil fields are important...and maybe Tehran).
We will need to give the Saudi Royal Family an offer they cannot refuse: Saudi Army participation in an attack or we support the Iraqi Army 2 years from now in taking Mekka after we liberate Iran ourselves.
One must understand that we actually allowed Saudi Arabia to not be onboard with the Iraq Liberation.
We could have told the Royals that we would f$*k them if they did not send the Saudi Army in to put down the Sunni insurgency. But we correctly saw the complications in having Saudis involved in Iraq. No such complications or excuses exist for Iran!
A big wildcard here is Venezuela and their open threats to cut off oil to the USA if an Iran invasion happens.
And we are still horribly weakened by our liberals who have been blocking the Alaska drilling for a generation.