The correct answer to this open question is the following.
The outcomes for the United States pre-and-post 9/11 were the following.
Pre 9/11, the United States had not paid so much attention to the terrorist groups of the Middle East that could have been infiltrated in American society. The major incident in this regard had been the bomb explosion outside the federal building Alfred Murrah, in Oklahoma City, on April 19, 1995.
But after the terrorist attacks of September 11, 2001, the Bush Administration reacted differently and the United States changed the security scheme that had prevailed in the past. President Bush ordered the creation of the Homeland Security Department and declared a war against terrorists, particularly against al Qaeda cell, in Afghanistan, and ordered the air raid in this country.