In late 2001, the United States and its close allies invaded Afghanistan and toppled the Taliban government. The invasion's aims were to dismantle al-Qaeda, which had executed the September 11 attacks, and to deny it a safe base of operations in Afghanistan by removing the Taliban government from power. The United Kingdom was a key ally of the United States, offering support for military action from the start of invasion preparations. The invasion came after the Afghan Civil War's 1996–2001 phase between the Taliban and the Northern Alliance groups, resulting in the Taliban controlling 80% of the country by 2001. The invasion became the first phase of the 20-year-long War in Afghanistan and marked the beginning of the American-led War on Terror. After the September 11 attacks, US President George W. Bush demanded that the Taliban hand over Osama bin Laden and expel al-Qaeda; bin Laden had already been wanted by the FBI since 1998. The Taliban declined to extradite him and ignored demands to shut down terrorist bases or extradite other suspected terrorists. The US launched Operation Enduring Freedom on October 7, 2001, with the United Kingdom. The two were later joined by other forces, including the Northern Alliance. The US and its allies rapidly drove the Taliban from power by December 17, 2001, and built military bases near major cities across the country. Most al-Qaeda and Taliban members were not captured, but escaped to neighboring Pakistan or retreated to rural or remote mountainous regions during the Battle of Tora Bora. In December 2001, the United Nations Security Council established the International Security Assistance Force (ISAF) to oversee military operations in the country and train the Afghan National Security Forces. At the Bonn Conference in December 2001, Hamid Karzai was selected to head the Afghan Interim Administration. Taliban leader Mullah Omar reorganized the movement, and in 2002 it launched an insurgency against the government and ISAF. In 2021, while international forces were withdrawing from the country after nearly 20 years of conflict, the Taliban succeeded in overthrowing the Afghan government and re-establishing their rule across much of Afghanistan. Background In 2001, Afghanistan had been at war for over 20 years. The communist People's Democratic Party of Afghanistan (PDPA) seized power in 1978, and its policies sparked a popular uprising. The Soviet Union, sensing PDPA weakness, intervened in 1979 to support the regime. The entry of the Soviet Union into