What Happen on September 11 2001?

On September 11, 2001 the United States suffered the first ever known terrorist attack. Nineteen terrorists hijacked American commercial jets and used them as weapons of mass destruction. Two were flown into the World Trade Center towers in New York City and one was crashed into the U.S. Pentagon in Arlington, Virginia. A fourth plane, believed to be headed for the White House, was crashed into a field in Pennsylvania when the passengers fought back.