Thus the impetus for a negotiated settlement. The problem with Mr. Trump’s Taliban deal wasn’t that the administration turned to diplomacy. That was a sensible avenue out of the policy constraints. The problem was that the strongest state in the international order let itself be swindled by a terrorist organization. Because we so clearly wanted out of Afghanistan, we agreed to disreputable terms, and then proceeded to pretend that the Taliban were meeting even those.

Mr. Trump agreed to withdraw all coalition forces from Afghanistan in 14 months, end all military and contractor support to Afghan security forces and cease “intervening in its domestic affairs.” He forced the Afghan government to release 5,000 Taliban fighters and relax economic sanctions. He agreed that the Taliban could continue to commit violence against the government we were there to support, against innocent people and against those who’d assisted our efforts to keep Americans safe. All the Taliban had to do was say they would stop targeting U.S. or coalition forces, not permit Al Qaeda and other terrorist organizations to use Afghan territory to threaten U.S. security and subsequently hold negotiations with the Afghan government.

Not only did the agreement have no inspection or enforcement mechanisms, but despite Mr. Trump’s claim that “If bad things happen, we’ll go back with a force like no one’s ever seen,” the administration made no attempt to enforce its terms. Trump’s own former national security adviser called it “a surrender agreement.”