The main reason the United States launched military operations in Afghanistan in October 2001 was to

The US military operations in Afghanistan in October of 2001 were a direct result of the terrorist attacks on 9/11. On September 11, 2001, members of the terrorist group Al Qaeda hijacked a plane and crashed it into the Twin Towers in New York city. This attack on US soil caused a strong reaction from President George W. Bush. Ultimately, the goal of the US involvement in Afghanistan was to find those individuals who organized this attack and to stop the spread of Al Qaeda's power in Afghanistan.