It began more than two decades ago. On September 20, 2001, President George W. Bush declared a “war on terror” and told a joint session of Congress (and the American people) that “the course of this conflict is not known, yet its outcome is certain.” If he meant a twenty-year slide to defeat in Afghanistan, a proliferation of militant groups across the Greater Middle East and Africa, and a never-ending, world-spanning war that, at a minimum, has killed about 300 times the number of people murdered in America on 9/11, then give him credit. He was absolutely right.

Days earlier, Congress had authorized Bush “to use all necessary and appropriate force against those nations, organizations, or persons he determine[d] planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001 or harbored such organizations or persons.” By then, it was already evident, as Bush said in his address, that al-Qaeda was responsible for the attacks. But it was equally clear that he had no intention of conducting a limited campaign. “Our war on terror begins with al-Qaeda, but it does not end there,” he announced. “It will not end until every terrorist group of global reach has been found, stopped, and defeated.”

Congress had already assented to whatever the president saw fit to do. It had voted 420 to 1 in the House and 98 to 0 in the Senate to grant an Authorization for Use of Military Force (AUMF) that would give him (and presidents to come) essentially a free hand to make war around the world.