All of these obstacles can be overcome with time and resources. But both ordinary citizens and the Taliban know that the United States will withdraw. It will withdraw for political reasons and because staying in Afghanistan is stupendously expensive. The U.S. military, carefully designed to inflict crushing high-intensity force, spends $1 million per year to put each soldier in Afghanistan. You don’t want to have been a tool of the United States when these forces are drawn down and the Taliban return to power.