During the early 2000s, the United States participated in the War in Afghanistan, which began in October 2001. This military intervention was primarily a response to the September 11 terrorist attacks, orchestrated by al-Qaeda, which was harbored by the Taliban regime in Afghanistan. The U.S. sought to dismantle al-Qaeda and remove the Taliban from power to prevent further terrorist activities. This conflict marked the beginning of the broader War on Terror, with American forces engaged in military operations, nation-building, and counterinsurgency efforts that significantly shaped U.S. foreign policy and military strategy for decades to come.