As the United States exits from Afghanistan, on the eve of the 20th anniversary of the 9/11 attacks, it is important to reflect on the broader and longer-term reverberations of that withdrawal. In examining the withdrawal, peace process, and the recent dynamic of militia building and Taliban control, it’s becoming clear that a different transnational threat to U.S. interests is emerging.

The U.S. has been mistaken in believing the Afghanistan war was ours to direct, and we are mistaken now if we think it is ours to “end.” The conflict has just entered a new phase with the international troop withdrawal. Instead of an environment we can help manage, the U.S. will be buffeted by the consequences of the predatory behavior of Afghanistan’s neighbors and non-state terror organizations. We now have nuclear-armed states competing for influence in Afghanistan with no NATO presence to mitigate their ferocity. We failed this test in the 1990s and paid for it in 2001. With that in mind, the best course for the U.S. is to reengage, rather than renege on our commitments, in order to protect our interests in this important region.