U.S. Secretary of State Colin Powell testifies before the 9/11 Commission.

NEW YORK CITY: 1080i HD AERIAL: NIGHT: TD WS lighted Ground Zero surrounded by buildings ZI/ZO empty area footprint World Trade Towers TD (moving north) over Ground Zero TU XWS New York City w/ Hudson River (L). PAN (R) ZI WS passing buildings.

U.S. Secretary of State Colin Powell testifies before the 9/11 Commission.

Former Secretary of State Madeleine Albright testifies before the 9/11 Commission in Washington, D.C.

Former Secretary of Defense William Cohen testifies before the 9/11 Commission in Washington, D.C.

At a session of the 9/11 Commission, co-chair Lee Hamilton says someone needs to manage bits and pieces of intelligence information.

A fire fighter's jacket with commemorating patch of World Trade Center tragedy hangs with other coats.

WORLD TRADE CENTER ON MONITORS: * HANDHELD: VS Monitors & screens in broadcast room showing World Trade Center Twin Towers in New York City (DATE: October 2000). 9/11, September 11, 2001, Terrorist attack, bombing.

A crane stands in position to remove debris from the fallen World Trade Center..

Rescue and cleanup operations continue at Ground Zero.

Rescue workers, including NYC police and firefighters, sift through the rubble of the World Trade Center towers.

Smoke billows from the rubble at Ground Zero in New York after the terrorist attacks of September 11th, 2001.

Rescue workers clear rubble at Ground Zero in New York after the terrorist attacks of September 11th, 2001.

An American flag hangs above the rubble at Ground Zero in New York.

An American flag hangs above the rubble at Ground Zero in New York.

Rescue workers and heavy machinery work on the rubble at Ground Zero in New York City after September 11, 2001.

Rescue workers and heavy machinery work on the rubble at Ground Zero in New York City after September 11, 2001.

Construction workers try to clear rubble at Ground Zero in New York City after September 11, 2001.

Construction workers try to clear rubble at Ground Zero in New York City after September 11, 2001.

Construction workers try to clear rubble at Ground Zero in New York City after September 11, 2001.

Construction workers use a crane to try and clear rubble at Ground Zero in New York City after September 11, 2001.

Construction workers try to clear rubble from Ground Zero in New York after the terrorist attacks of September 11, 2001.

Construction workers try to clear rubble from Ground Zero in New York after the terrorist attacks of September 11, 2001.

Construction workers try to clear rubble from Ground Zero in New York after the terrorist attacks of September 11, 2001.

Construction workers try to clear rubble from Ground Zero in New York after the terrorist attacks of September 11, 2001.