Starting late in 2004, I have been writing that the United States could not rationally comtemplate attacking Iran. (For reasons laid out in 2004, 2006, and 2007.) Through that time I have been arguing with friends, adversaries, and people I do not know, all of whom keep saying: rational or not, it's coming!

This dispute is strange in one obvious way.

In saying that the United States might huff and puff but finally not go to war, I have had the impossible challenge of proving a negative. Sure, the United States hasn't attacked up until today. But that's no proof that it won't attack tomorrow! All I have on my side is the long list of past "crying wolf" predictions, especially the flurry of warnings last summer that the Bush Administration was "sure" to attack by October to save its party in the mid-term elections.

But there is a deeper strangeness that I worry about at 2 a.m. Am I guilty of projecting my own assumptions about rationality onto the Administration?

Based on everything I have learned through reporting, or simply read and thought, an attack on Iran would be unique in modern American history -- perhaps in the entirety of American history. American leaders have made a lot of mistakes in 200-plus years. (Plus made a lot of inspired, far-seeing decisions.) But they have rarely done things that were simply insane.

Example one: the deepening commitment in Vietnam was a horrible strategic error for the United States. But at every step of the way someone offered seemingly-logical reasons to take another step. (This was the point of Leslie Gelb's and Richard Betts' book, The Irony of Vietnam: The System Worked.)

Example two: the invasion of Iraq and the deepening commitment there amount to a horrible strategic error for the United States. But at least in the early stages people offered seemingly-logical reasons for going ahead. The judgments based on these reasons were wrong, and should have been seen as such at the time. But they were not simply nuts. (I say this even remembering the way I quoted a British spy in the Atlantic, six months before the war. He called the dreams of democratizing Iraq "the ruminations of insane people.") The mismanagement of the occupation reflected grievous incompetence, carelessness, and self-delusion, but, again, not insanity.

Examples three and four: If Richard Nixon had tried to seize control of the military rather than leave office in 1974, or if Dwight Eisenhower had said "bombs away!" to General Curtis LeMay's suggestions in the 1950s that the Soviet Union should be attacked before it got too strong, the American leadership could have been considered insane. But neither of those things occurred.

Launching a discretionary war against Iran would be insane. Every one of the elements of long-term American strength and self-interest would be jeopardized: Economic, grand-strategic, diplomatic, military, moral. There would be damage in the short run -- stepped-up attacks in Iraq, chaos in the oil market -- and worse damage for decades to come.

For all these reasons, I have not quite believed that even an administration as guilty of misjudgments as this one would actually go ahead and start such a suicidal war. I know that I said something slightly different recently -- "no one can any longer trust the Administration to recognize and defend America's rational self-interest," and so on -- but, down deep, I haven't been willing to think that people in positions of responsibility would take such a forseeably irresponsible step. That is, I have thought that George Bush and Dick Cheney were as decent as Richard Nixon.

Am I the irrational one here, in assuming others' rationality? I hope not -- and I still think not. But just in case I'm wrong, the Congress should get moving and pass that "no funds for war with Iran" measure without delay.

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