Twenty-five years after Sept. 11, the scale still stops the clock: 2,977 people were killed in New York, Virginia and Pennsylvania.
The attacks began at 8:46 a.m., when American Airlines Flight 11 hit the North Tower of the World Trade Center. At 9:03 a.m., United Airlines Flight 175 hit the South Tower. At 9:37 a.m., American Airlines Flight 77 hit the Pentagon. At 9:59 a.m., the South Tower collapsed. At 10:28 a.m., the North Tower collapsed.
Flight 93 never reached its intended target. Passengers fought back, and the plane crashed in Pennsylvania instead of into a building full of people.
The attacks killed 343 NYFD firemen and 23 NYPD policemen responding at the World Trade Center, according to the source. NATO allies invoked Article 5 in Brussels, saying an attack on America was an attack on all and committing troops to fight al-Qaeda and the Taliban in Afghanistan.
Osama bin Laden emerged as the mastermind of the attacks, and U.S. special forces killed him in 2011 in a raid in Pakistan.
The big picture: 9/11 did more than destroy buildings. It launched decades of counterterror and counterinsurgency operations across the Middle East and defined American national security policy for a generation. Hundreds of thousands of Americans deployed, and thousands were killed in combat.
Why it matters: remembering the date is not nostalgia. It is a reminder that state power, intelligence and military readiness exist for moments when the country is attacked. That lesson still matters as the next generation grows up far from the smoke, the debris and the cost.