This bill requires the Inspector General of the Department of Defense to conduct a full investigation into the withdrawal of the U.S. Armed Forces from Afghanistan. The investigation must analyze (1) the extent to which, and reasons why, U.S. Humvees, helicopters, artillery, and drones ended up in the Taliban's possession; (2) the extent to which Afghan forces in possession of U.S. equipment entered Iran with such equipment; and (3) the effectiveness of the evacuation of U.S. and allied personnel.