Robert Dallek warns Obama of the three historical myths that have ruled American military engagement over the last century:

Obama seems keenly aware of the main lesson of Vietnam: Don't let the appeasement metaphor, cliché, conviction, call it what you will, lock you into an unwinnable war that destroys your presidency. He appreciates that a grand design or strategy in foreign affairs does not readily translate from one crisis to another. Appeasement was a terrible idea in dealing with Hitler, but avoiding it was never the right argument for crossing the 38th parallel in Korea or embroiling the United States in Vietnam. (After all, a stalemate in the first war and a defeat in the second did not deter the United States from winning the larger Cold War.) Nor is Obama persuaded by grand Wilsonian visions of bringing democracy to Iraq and Afghanistan; he has made clear that he does not see military solutions to the problems America faces in those two countries. He has openly described the invasion of Iraq as a "mistake" and seems determined to de-escalate U.S. involvement in Afghanistan as soon as possible.

But no matter how conscious Obama is of the perils of history's traps, he faces no small challenge in convincing political opponents to relinquish the outworn foreign-policy clichés that have been of such questionable service to America's well-being. As Germany's Otto von Bismarck is said to have observed more than 100 years ago, great statesmen have the ability to hear, before anyone else, the distant hoofbeats of the horse of history. More often than not, however, it is the accepted wisdoms -- or the wrong lessons of history altogether -- that govern the thinking of publics and the behavior of their leaders.

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