The rhetoric toward war is increasing between the United States and Iran. The prospect of further sanctions against Iran, coupled with the Iranian promise that, if this happens, Iran will close the Strait of Hormuz, has upped the ante. American troops are out of Iraq, which frees up at least some American troops. Since the U.S. has gone from Iraq, and since Iraq has no air force, Israel now has more or less a straight shot at the Iranian target.
Apart from the question, never asked and never answered, as to why Iran cannot have nuclear weapons while India and Pakistan can, there is the lassitude that has set in over the successive wars in Afghanistan -- which has lasted much too long -- and Iraq -- which has been essentially fruitless. A new war is certainly to be avoided, if possible.
I think we have to live with the prospect that Iran is going to acquire nuclear weapons, and that we should, while remaining constantly on guard, consider that the powerful U.S. deterrent will dissuade Iran from ever using such weapons. Given Iran's long history of submission and deception (the latter known in Farsi as takiya), this would seem not to be an unreasonable premise. In other words, Iranian threats overall should be taken, without evidence to the contrary, as bluff. Of course it would have been better if the threats had not been there in the first place. It was Ahmedinejad's apocalyptic rhetoric against Israel that began this unfortunate escalation.
What worries us all, of course, is the possibility of a skirmish in the Persian Gulf, inadvertent or otherwise. Hopefully such an incident might be contained to a U.S. tactical intervention, as escalation to a full war would be disastrous.
Since regime change in Iran is out of reach for the Western powers, we must for the foreseeable future deal with a situation in which Khamenei and the Revolutionary Guards rule Iran.
In all this, the U.S. grudge against Iran should be kept under control. Though the Iran hostage crisis of 1979-1980 ended unsatisfactorily from the point of view of U.S. honor, a great power needs to get beyond residual rancors.
Charles Cogan was the chief of the Near East-South Asia Division in the Directorate of Operations of the CIA from August 1979 to August 1984, a tenure that included the 444 days of the Iran hostage crisis. He is now an historian and an associate of the Belfer Center's International Security Program at the Harvard Kennedy School.