Iran’s mullahs will use nuclear weapons as a shield against foreign attack while they more openly support terrorism elsewhere. American acquiescence in Iranian nuclear weapons will lose the war on terror by ceding terrorists a “privileged sanctuary” in Iran. We’ll have let terrorists have in Iran what we invaded Iraq to stop. The invasion of Iraq will have been a complete waste of effort, and our dead in Iraq will have died in vain.

More here. A few too many instances of "possibly", "might", "I feel" etc. for my liking. I don't think allowing the Iranian mullahs their own nuclear arsenal is tolerable, though, and negotiation and diplomacy don't seem to have worked so far. Alternatives?