At 8:46 a.m., American Airlines Flight 11 struck the North Tower of the World Trade Center. Seventeen minutes later United Flight 175 hit the South Tower. A third plane hit the Pentagon, and a fourth, United 93, crashed in a Pennsylvania field after passengers fought back. Both towers collapsed within two hours, killing 2,753 people in New York alone. The attacks reshaped American foreign policy, launching the 'War on Terror' and the invasions of Afghanistan and Iraq.
Nineteen al-Qaeda hijackers had trained for months, some at flight schools in Florida, funded and directed by Osama bin Laden from Afghanistan. Air traffic controllers first suspected a tragic accident when Flight 11 vanished from radar after turning off its transponder; within minutes, live television showed the truth to a stunned world as the second plane struck.
Inside the towers, thousands descended stairwells in an orderly exodus even as fire and smoke consumed the floors above the impact zones. Firefighters climbed upward past them, 343 of whom would not come back down. Todd Beamer's words aboard Flight 93, 'Let's roll,' became a rallying cry after passengers stormed the cockpit, denying hijackers a fourth target believed to be the U.S. Capitol.
The South Tower fell first, at 9:59 a.m., in under 10 seconds, followed by the North Tower at 10:28. Dust coated lower Manhattan in a grey shroud that became the day's defining image. The attacks led directly to the creation of the Department of Homeland Security, the USA PATRIOT Act, and two decades of war that reshaped geopolitics across the Middle East and Central Asia.