The Trump administration has signed an interim deal with the Taliban to end the war in Afghanistan. The basic contours of the deal are as follows: the Taliban agree to not allow al-Qaeda or any other group to use Afghan territory to conduct international terrorism against the United States or its allies, and in return the United States will withdraw its military forces from the country. Within 135 days, the Trump administration will reduce the number of U.S. forces in Afghanistan from approximately 13,000 today to 8,600. The remainder will be withdrawn within 14 months, contingent on the Taliban’s fulfillment of its side of the bargain, which includes a prisoner exchange, verifying that it is taking measures against foreign terrorist groups on Afghan soil, and starting intra-Afghan negotiations with the U.S.-backed regime in Kabul.

The good news is that we have never been this close to ending the war. The futility of the U.S. mission in Afghanistan has become so undeniable that full withdrawal has finally become politically viable. The bad news is that this deal could have been made back during the Bush administration. Unfortunately, political leaders in Washington, DC, reluctant to take political risks and paralyzed by the uncertainties of withdrawal, perpetuated a lost cause for well over a decade.

A more forward-looking concern is the uncomfortable fact that this deal makes U.S. withdrawal too conditional. Although the text of the deal appears to make U.S. withdrawal dependent only on the Taliban’s severance of ties with al-Qaeda and related groups, Defense Secretary Mark Esper explained that “If progress on the political front between the Taliban and the current Afghan government continues, then the United States and its partners will further reduce our presence toward a goal of zero in 2021. If progress stalls, then our drawdown likely will be suspended, as well.”

President Trump himself emphasized this just hours after the agreement was signed: “If bad things happen, we’ll go back.” And Secretary of State Pompeo, too, clarified the contingent nature of the deal: “The agreement will mean nothing — and today’s good feelings will not last — if we don’t take concrete action on commitments stated and promises made.”

If the Trump administration is truly making U.S. withdrawal contingent on the Taliban and Kabul successfully signing a power-sharing peace agreement, it could very well be the death knell for the deal. We are already seeing cracks: Afghan President Ashraf Ghani said on Sunday that he rejects the idea of a Taliban-Kabul prisoner swap, which is supposed to be carried out by March 10. He said the United States was in no position to make that promise on his behalf. The text of the deal says, “The United States commits to completing this goal,” but our own partner on the ground has dismissed it outright. In response, the Taliban declared they would not engage in intra-Afghan peace talks before a prisoner exchange has taken place.

Even as America announces her impending withdrawal from Afghanistan, she still helplessly clings to the very fantasies that have kept her bogged down in this quagmire for nearly 20 years. We have not remade Afghan politics. We have not established a stable, democratic, independent government in Kabul. We have not defeated the Taliban. Neighboring Pakistan still fuels militancy and provides safe haven to insurgent groups. Making U.S. withdrawal dependent on rosy relations between Afghanistan’s warring factions only serves to provide another bad excuse to continue a lost cause. Afghanistan is more likely than not to experience violence and instability following a U.S. withdrawal. But that does not vitiate the wisdom of withdrawal. After nearly 20 years, $2 trillion, and an immense loss of life, it is now a vital national interest to end the war. But if the war doesn’t end within 14 months, exiting the war should be the priority, regardless of conditions on the ground.

For more on why we can afford to do just that, see this Policy Analysis I co-authored with John Mueller back in August: Overcoming Inertia: Why It’s Time to End the War in Afghanistan.