It recounts a chain of strategic and political decisions in August 2021 that culminated in the shocking scenes the world witnessed at Kabul Airport and the bombing of Abbey Gate, where 13 U.S. troops and hundreds of Afghan civilians died as the final American planes left the country and the Taliban retook the capital. President Biden ordered the military to withdraw completely before September 11, 2021 -- 20 years after the 9/11 attacks -- while many military officials suggested keeping control of Bagram Airfield.