The invasion of afghanistan by american troops was

The invasion of Afghanistan by American troops was a response to the 9/11 attacks.

Explanation:

The War in Afghanistan of 2001-2014 began with the US-led intervention in the fall of 2001. The United States government (the Bush administration under George W. Bush from 2001 to 2009) and its allies pursued the goal of overthrowing the Taliban government, which had been ruling since 1996, and of fighting the terrorist organization al-Qaeda. The latter was blamed for the terrorist attacks on September 11, 2001. To this end, the United States entered into an alliance in Afghanistan with the United Front's anti-Taliban alliance, whose troops attacked the Taliban with US air support on October 7, 2001. This phase of the war ended with the conquest of the capital Kabul and the provincial capitals of Kandahar and Kunduz in November and December 2001 by the United Front. This was followed by the establishment of an interim government under President Hamid Karzai.

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