FBI: Suicide bombs are a big concern

Suicide bombers have not hit the United States since the 9/11 terrorist hijacking attacks, but they remain a constant concern because of their prevalence around the globe and determination to die for their causes, according to the FBI's chief of counterterrorism. He does not believe America is overflowing with homegrown terrorists, but Joseph Billy said "a significant number" of attacks have been thwarted since airliners were crashed into the World Trade Center, the Pentagon and a Pennsylvania farm field on September 11, 2001.