What major event happened on September 11, 2001?

The major event that occurred on September 11, 2001, was the terrorist attacks on the United States. This day is marked by a coordinated effort by the extremist group al-Qaeda, which resulted in the hijacking of four commercial airplanes. Two of these planes were flown into the World Trade Center towers in New York City, causing their eventual collapse. A third plane struck the Pentagon, while the fourth, United Flight 93, was headed towards a target in Washington D.C. but crashed in Pennsylvania after passengers attempted to overcome the hijackers.

This tragic event led to significant loss of life, with nearly 3,000 people killed, and it also had lasting impacts on U.S. domestic and foreign policy, including increased security measures and the initiation of the War on Terror. The September 11 attacks fundamentally changed the global landscape and marked a pivotal moment in U.S. history, making it a significant event that is remembered and commemorated each year.

The other events mentioned—World War II ending, the Great Depression, and the signing of the Declaration of Independence—are important historical milestones, but they occurred long before 2001 and are unrelated to the events of September 11th.