I don't see what the issue is with invading Iran. They're heavily supporting terrorists who are killing our soldiers in Iraq and Afghanistan. Intelligence has shown they are actively developing nuclear weapons.
What more do we need to justify an attack?
Careful with this rationalization...and here's why...
Pakistan ALREADY has nuclear weapons. Osama Bin Laden escaped during a cease-fire via Tora Bora into, yes, Pakistan. So, with your logic, we should've already invaded Pakistan.
Why haven't we done this?? They cannot reach us with nukes via missiles. Why have we not invaded??
Also be careful with the Islamic Facism argument as well. As much as I agree that radicals have taken over Islam, we have done much since our intervention in Iran in the 1950's to bring this about. If we use the Islam argument, we will need to invade all of North and East Africa, the Middle East, Malaysia, Chechnya, Pakistan, all of the other -stans, Turkey, etc., etc....
Imagine if we spent all of the defense money from Iraq, and secured the borders, as well as worked on R&D for WMD device detection at our customs offices. We could already be ahead of the game DEFENDING ourselves, rather than going on offense while still having porous borders...