On September 11, 2001, a terrorist group known as Al-Qaeda carried out a series of coordinated attacks on the United States. The attacks involved the hijacking of four commercial airliners, with two of them being flown into the Twin Towers of the World Trade Center in New York City and one into the Pentagon in Washington, D.C. A fourth plane crashed in a field in Pennsylvania after passengers attempted to overpower the hijackers.

The attacks resulted in the deaths of nearly 3,000 people, including the passengers on the planes and the individuals working in the targeted buildings. It was the deadliest terrorist attack in world history and the single deadliest day for firefighters and law enforcement officers in American history.

The 9/11 attacks had a profound impact on the United States and the world. It sparked widespread fear and confusion, and led to major changes in U.S. national security and foreign policy. It also led to the passage of the USA PATRIOT Act, which expanded the government’s surveillance powers and ability to search for terrorists.