It all started at 8:45 on a clear Tuesday morning. A passenger plane had flown into the World Trade Center's North Tower. Then, a second plane flew into the other tower.
Airports, bridges, tunnels in New York and New Jersey shut down.
Within 30 minutes, President George W. Bush said we were under an "apparent terrorist attack," and minutes after that, every airport in the country was closed.
At 9:43 AM, a third passenger jet crashed into the Pentagon. Dark smoke rolled up from the side of the building. All eyes, and many cameras, were on that and the two burning towers in New York.
At 10:05, one of those towers gave way where it was smoking, the top part crushing down on the rest of it and sending up debris in boiling gray clouds.
Five minutes later, part of the Pentagon collapsed, and a fourth hijacked jet crashed in a rural part of Pennsylvania.
The White House, the United Nations, the state and justice departments, the world bank -- all evacuated. America-bound Atlantic flights were rerouted to Canada.
At 10:28 the second trade center tower came down.
Except for emergency response teams, the country virtually stopped what it was doing and gathered around television screens. The president appeared just after 1 PM and asked Americans to pray.
The destruction was more or less done around 10:30 AM. It was less than two hours from the first crash, but the change it inflicted was immeasurable. More americans were killed on September 11th, 2001 than on the Japanese attack on Pearl Harbor in 1941.
When President Bush addressed the nation that night at 8:30, his tone was one of sympathy, resolve and warning to anyone who'd planned or supported the attacks.
In the difficult days that followed, it was learned that the al-Qaeda terrorist group, led by Osama bin Laden, was responsible.
America's attention and anger turned to Afghanistan, whose Taliban leaders were giving al-Qaeda a safe place to live and operate.