Centers for Disease Control and Prevention

“ Terrorism is not new. It’s been around as long as people have been willing to use violence as a political weapon. Title 22 of the United States Code, Section 2656f (d) , defines terrorism as the “premeditated, politically motivated violence perpetrated against noncombatant targets by subnational groups or clandestine agents, usually intended to influence an audience.
The types of terrorist attacks discussed in this section are rare and usually relatively limited in scope. ”

“ On September 11, 2001, several thousand people died from the air attacks on the World Trade Center, the Pentagon, and on the plane near Shanksville, Pennsylvania. Thousands more, including first responders, area residents, and workers, were exposed to potentially dangerous chemicals in the dust and ash clouds in Manhattan. ”