Commentary In the first two weeks of August, America’s withdrawal from Afghanistan became a humiliating rout. Make no mistake, the United States has suffered a major diplomatic and psychological defeat that will have resonance throughout the world. Understand that I think that since 9/11, America’s essential mission in Afghanistan has been what I call Guard Duty Writ Large. I first used that description in 2012. To protect U.S. national security at home and abroad, America had to attack and damage militant Islamic terrorist organizations. That meant denying them bases in anarchic regions, like Yemen, Somalia, and Afghanistan. Denying doesn’t mean we have to occupy those places. It definitely doesn’t mean we need to engage in nation building and culture-changing—those are mega-challenges. We can strike Yemen and Somalia from the sea. Landlocked Afghanistan presents a problem. The closest air bases are six to seven hours away. Guard duty in Afghanistan means—or …