The 9/11 attacks were not the first attacks of the 21st century; in 2000, the bombing of the USS Cole occurred. A couple of events that led up to the 9/11 attacks include the bombing of the United States Marine Corps barracks in Beirut, Lebanon in 1983 and the bombing of the World Trade Center in 1993.
The magnitude of this attack was felt around the world. Al-Queda’s attack on America this time was successful on multiple levels. The fear American’s