The Afghan debacle doesn’t create a crisis of belief in American military credibility. Informed global observers don’t doubt our willingness to strike back if attacked. The debacle feeds something much more serious and harder to fix: the belief that the U.S. cannot develop—and stick to—policies that work.

Neither allies nor adversaries expected perfection in Afghanistan. Mr. Biden was right to say that the end of a war is inevitably going to involve a certain amount of chaos, and world leaders likely didn’t anticipate a seamless transition. They did, however, expect that after two decades of intimate cooperation with Afghan political and military forces, the U.S. wouldn’t be blindsided by a national collapse. They didn’t think Washington would stumble into a massive and messy evacuation crisis without a shadow of a plan. They didn’t expect the Biden team to have to beg the Taliban to help get Americans out.

It all fuels fears that the U.S. is incapable of persistent, competent policy making in ways that will be hard to reverse. It seems increasingly evident that despite, or perhaps because of, all the credentialed bureaucrats and elaborate planning processes in the Washington policy machine, the U.S. government isn’t good at producing foreign policy. “Dumkirk,” as the New York Post called the withdrawal, follows 20 years of incoherent Afghanistan policy making. Neither the past two decades nor the past two weeks demonstrate American wisdom or the efficacy of the byzantine bureaucratic ballet out of which U.S. policy emerges.