War in Afghanistan
Also called: Operation Enduring Freedom, War on Terror
After the September 11 attacks the United States attacked and toppled the Taliban regime that had sheltered al-Qaeda in October 2001. The war lasted twenty years; when US forces left in 2021 the Taliban took the country again.

Master Sgt. Chris Spence, FOB-53/U.S. Army, United States Special Operations Command · Public domain · Source
When the Taliban refused to hand over bin Laden, the United States and Britain began bombing Afghanistan on 7 October 2001. On the ground, US special forces and CIA officers rode on horseback with the Northern Alliance, which had been fighting the Taliban, and called in air strikes. Kabul fell on 13 November and Kandahar, the Taliban heartland, in early December.
That December bin Laden was cornered in the caves of Tora Bora in the eastern mountains but slipped away into Pakistan. NATO invoked for the first time its clause that an attack on one member is an attack on all and joined the fight; South Korea also sent medical and engineering units.
A new government was formed, but the Taliban regrouped and the conflict became the longest war in American history. When US forces withdrew in August 2021, the Taliban entered Kabul once more.

