The major event that happened in the United States on September 11, 2001 was called the 9/11. The 9/11 had 11 attacks caused by terrorists. There were even suicide attacks. And in the end, a total of 2,977 people were killed in New York City, Washington, D.C., and Shanksville, Pennsylvania, in the most terrible terrorist attack in U.S. history.
Hope I helped!
- Debbie