Andrew J. Bacevich is professor of history and international relations at Boston University.

Once the capital of a nation defined by inalienable rights; government of, by, and for the people; Fourteen Points; Four Freedoms; and “Mr. Gorbachev, tear down that wall!,” Washington is today preoccupied with Anthony Weiner’s crotch and parsing Sarah Palin’s interpretation of Paul Revere’s ride as a defense of the Second Amendment. What used to be known as the people’s business is today becoming indistinguishable from farce. Whether our ruling class possesses the ability even to identify the matters deserving the attention of senior policymakers has become an open question.

Take Afghanistan, for example. A promised presidential decision on withdrawing some indeterminate number of troops—presumably initiating a process, again of indeterminate length, aimed at ending the war altogether—is forthcoming. A big deal? Not really. In fact, the question of troops levels in the war zone is barely worthy of presidential attention. Barack Obama should have more important things to attend to.

If the Afghanistan War is essential to the safety and well-being of the American people, then the president should allow the commanders entrusted with its prosecution considerable discretion in deciding both what they need to accomplish their assigned mission and how long it will take. Let Gen. David Petraeus make the call on the rate of withdrawal—on whether to withdraw any troops at all. If the president lacks confidence in Petraeus’s ability to manage the war, then he should find himself a new general.

If, on the other hand, the Afghanistan War is not essential to the safety and well-being of the American people—a position to which I subscribe—then the imperative is to end that war forthwith. We’ve already wasted too much money and too many lives in the “graveyard of empires.” Should General Petraeus entertain a different view, then the president should find himself a four-star willing to do the commander in chief’s bidding. As for the specific schedule of withdrawal, establish basic parameters and let the military figure out the details. Having Obama decide how many troops should come home this summer makes about as much sense as having LBJ and Robert McNamara pick bombing targets in North Vietnam...