On September 20, 2001 after an investigation by the FBI the U.S. concluded that Al Qaeda and Osama bin Laden were behind the September 11, 2001 attacks. The U.S. made a five point ultimatum to the Taliban:
deliver to the US all of the leaders of Al Qaeda;
Release all imprisoned foreign nationals;
Close immediately every terrorist training camp;
Hand over every terrorist and their supporters to appropriate authorities;
Give the United States full access to terrorist training camps for inspection [15].
The Taliban rejected this ultimatum on September 21, 2001, stating there was no evidence in their possession linking Bin Laden to the September 11 attacks [16].
On September 22, 2001, the United Arab Emirates and later Saudi Arabia withdrew their recognition of the Taliban as the legal government of Afghanistan, leaving neighboring Pakistan as the only remaining country with diplomatic ties. On October 4, 2001, it is believed that the Taliban covertly offered to turn Bin Laden over to Pakistan for trial in an international tribunal that operated according to Islamic shar'ia law [17]. Pakistan is believed to have rejected the offer. On October 7, 2001, before the onset of military operations, the Taliban made an open offer to try Bin Laden in Afghanistan in an Islamic court[18]. This counter offer was immediately rejected by the U.S. as insufficient.
Shortly afterward, on October 7, 2001, the United States, aided by the United Kingdom and supported by a coalition of other countries including several from the NATO alliance, initiated military actions, code named Operation Enduring Freedom, and bombed Taliban and Al Qaeda related camps[19][20]. The stated intent of military operations was to remove the Taliban from power because of the Taliban's refusal to hand over Osama bin Laden for his involvement in the September 11 attacks, and disrupt the use of Afghanistan as a terrorist base of operations[21]. On October 14 the Taliban openly counteroffered to hand Bin Laden over to a third country for trial, but only if the Taliban were given evidence of Bin Laden's involvement in 9/11[22]. The U.S. rejected this offer as an insufficient public relations ploy and continued military operations.
The ground war was mainly fought by the Northern Alliance, the remaining elements of the anti-Taliban forces which the Taliban had routed over the previous years but had never been able to entirely destroy. Mazar-i-Sharif fell to U.S.-Northern Alliance forces on November 9, leading to a cascade of provinces falling with minimal resistance, and many local forces switching loyalties from the Taliban to the Northern Alliance. On the night of November 12, the Taliban retreated south in an orderly fashion from Kabul. This was sufficiently orderly, that on November 15, they released eight Western aid workers after three months in captivity (see Attacks on humanitarian workers). By November 13 the Taliban had withdrawn from both Kabul and Jalalabad. Finally, in early December, the Taliban gave up their last city stronghold of Kandehar and retired to the hilly wilderness along the Afghanistan - Pakistan border, where they remain today as a guerilla warfare operation, drawing new recruits and developing plans for a restoration of power.