... FROM DRESDEN TO DUNKIRK TO DETROIT, the generation that lived through the war is now dead or very elderly, in their late 80s and 90s. Their children are nearing retirement age, and it’s their grandchildren and great-grandchildren who now make up the bulk of the population. Usually, this passage of time would be the point at which memory ends and history begins. Yet the Third Reich remains as significant as ever, not just as a point of reference but as a period that has defined an entire policy framework.

An old, Cold War–era joke about NATO says that it was designed to keep the Americans in, the Russians out—and the Germans down. The Cold War is over, but the existence of the Nazi past remains a dominant algorithm in the operating system of international relations. That’s especially the case for Germany itself, which shelters behind its history as an excuse to punch below its weight, or not punch at all. But it’s also true elsewhere, including in the United States.

When George W. Bush ordered the invasion of Iraq in 2003, he explicitly compared Saddam Hussein to Adolf Hitler, and invoked parallels to the 1938 Nazi occupation of Czechoslovakia. The Bush-Cheney vision for postwar Iraq was strikingly similar to the 1945 template for postwar Germany—one which expected that the Iraqis would welcome American troops into their nation with open arms, thrilled that the tyrannical dictator had fallen, and be eager for the United States to preside over Iraq’s reemergence as a peaceful and democratic country. Efforts to rebuild Iraq after the war were inevitably referred to as a “Marshall Plan,” evoking the spirit of the American economic aid package that had financed the successful reconstruction of postwar Europe.

The Obama administration continues to use the same reference framework. In September 2013, as he considered options for dealing with Syrian president Bashir al-Assad’s use of chemical weapons, Secretary of State John Kerry described the situation as “our Munich moment,” a reference to the 1938 attempt by Britain and France to appease Hitler by permitting Nazi’s Germany’s partial annexation of Czechoslovakia. In March, after Russia’s move on Crimea, it was former Secretary of State Hillary Clinton’s turn. At a private fundraiser in California, she likened Vladimir Putin’s campaign to provide Russian passports to ethnic Russians living outside Russia’s borders to Hitler’s protection of ethnic Germans in the Sudetenland.

Such historical parallels actually do everyone a disservice. Saddam Hussein, Bashir al-Assad and Vladimir Putin are not Hitler, any more than they are Genghis Khan, Attila the Hun, or Ivan the Terrible. As Bush and Cheney found, Iraqis are not Germans, and 2014 Baghdad is nothing like 1945 Berlin. Sticking to this reference framework is a simplistic and lazy way to avoid facing the tough questions based on today’s reality....