The September 11 attacks, commonly known as 9/11,[e] were four coordinated Islamist suicide terrorist attacks carried out by al-Qaeda against the United States on September 11, 2001. That morning, 19 terrorists hijacked four commercial airliners scheduled to travel from the East Coast to California. The hijackers crashed the first two planes into the Twin Towers of the World Trade Center in New York City, two of the world's five tallest buildings at the time, and aimed the next two flights toward targets in or near Washington, D.C., in an attack on the nation's capital. The third team succeeded in striking the Pentagon, the headquarters of the U.S. Department of Defense in Arlington County, Virginia, while the fourth plane crashed in rural Pennsylvania during a passenger revolt. The September 11 attacks killed 2,977 people, making them the deadliest terrorist attack in history, and instigated the multi-decade global war on terror, fought in Afghanistan, Iraq, and elsewhere.
The first impact was that of American Airlines Flight 11, which ringleader Mohamed Atta flew into the North Tower of the World Trade Center complex in Lower Manhattan at 8:46 a.m.[f] Seventeen minutes later, at 9:03,[g] the World Trade Center's South Tower was hit by United Airlines Flight 175. Both 110-story skyscrapers collapsed within an hour and forty-one minutes,[h] bringing about the destruction of the remaining five structures in the WTC complex and damaging or destroying nearby buildings. A third flight, American Airlines Flight 77, crashed into the Pentagon at 9:37 a.m., causing a partial collapse. The fourth and final flight, United Airlines Flight 93, flew in the direction of the capital. Alerted to the previous attacks, the passengers fought for control, forcing the hijackers to nosedive the plane into a Stonycreek Township field, near Shanksville, at 10:03 a.m. Investigators determined that Flight 93's target was either the United States Capitol or the White House.