Changes

The Taliban was a Sunni Islamic fundamentalist movement which effectively ruled most of Afghanistan from 1996 until 2001, when United States forces invaded Afganistan and overthrew them. The world means "students"

The Taliban was a Sunni Islamic fundamentalist movement which effectively ruled most of Afghanistan from 1996 when the United States assisted them until 2001, when United States forces invaded Afganistan and overthrew them. The world means "students"

The reason for invasion was that the Taliban had ties to al-Qaida (a militant Sunni Islamist organization), the group that is held responsible for the attacks on America, September 11th, 2001.  

The reason for invasion was that the Taliban had ties to al-Qaida (a militant Sunni Islamist organization), the group that is held responsible for the attacks on America, September 11th, 2001.