The September 11 attacks, commonly referred to as 9/11, were a series of four coordinated suicide terrorist attacks carried out by the Islamist extremist group al-Qaeda against the United States on the morning of Tuesday, September 11, 2001. [1, 2, 3]

Events of the Day

Nineteen terrorists hijacked four commercial airplanes, turning them into guided missiles. [1, 2]

• 8:46 a.m. – World Trade Center (North Tower): American Airlines Flight 11 struck the North Tower in New York City.

• 9:03 a.m. – World Trade Center (South Tower): United Airlines Flight 175 struck the South Tower.

• 9:37 a.m. – The Pentagon: American Airlines Flight 77 crashed into the western side of the Pentagon in Arlington, Virginia.

• 10:03 a.m. – Shanksville, PA: United Airlines Flight 93 crashed in a field after passengers and crew heroically fought back against the hijackers. Its intended target is believed to have been either the U.S. Capitol or the White House. [1, 2, 3, 4, 5]

Casualties and Impact

• Loss of Life: A total of 2,977 victims were killed. This included:

  • 2,753 people in New York City (including 343 firefighters and 60 law enforcement officers).

  • 184 people at the Pentagon.

  • 40 people on Flight 93.

• Health Consequences: Thousands of survivors and first responders continue to suffer from 9/11-related illnesses, including cancer and respiratory diseases, due to toxic dust exposure. Recent reports from May 2026 note that former NYC Mayor Rudy Giuliani has been hospitalized with pneumonia aggravated by his long-term 9/11-related airway disease.

• Structural Changes: The attacks led to the creation of the Department of Homeland Security and significant changes in global airport security. [1, 2, 3, 4, 5, 6, 7]