September 11 attacks
The September 11 attacks (also referred to as 9/11) were a series of four coordinated terrorist attacks by the Islamic terrorist group al-Qaeda against the United States on the morning of Tuesday, September 11, 2001. The attacks killed 2,996 people, injured over 6,000 others, and caused at least $10 billion in infrastructure and property damage. Additional people died of 9/11-related cancer and respiratory diseases in the months and years following the attacks.
Security theater
Two studies by a group of Cornell University researchers have found that strict airport security in the United States after the 9/11 attacks has the unintended consequence of increasing road fatalities, as would-be air travelers decide to drive and are exposed to the far greater risk of dying in a car accident. In 2005, the researchers looked at the immediate aftermath of the attacks of September 11, 2001, and found that the change in passenger travel modes led to 242 added driving deaths per month. In all, they estimated that about 1,200 driving deaths could be attributed to the short-term effects of the attacks.