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After the Taliban Government of Afghanistan failed to adequately respond to US diplomatic offers, George Bush invaded Afghanistan.
Although covert US forces had been in Afghanistan within days of 911, the conventional forces that would initiate the beginning of the war began sorties on Oct. 7. After the Afghan government had refused to speak to US diplomats and continued to publicly defend Osama Bin Laden, most Arab nations broke off diplomatic relations with them.
The UN Security Council did not have to authorize the use of force in the NATO-led military operations in Afghanistan as it was an act of collective self-defense provided for under Article 51 of the UN Charter. The Security Council has, however, authorized the International Security Assistance Force to use force in its mission of securing the country.