Smoke billowed from the Pentagon for days following the Sept. 11 attack
The Defense Department has since created a memorial in the rebuilt wedge to honor the people who lost their lives there that day'on the ground and aboard American Airlines Flight 77.
President Bush, who visited the site to thank the cleanup team, adopted the 'Let's roll' phrase for the war on terrorism from the passengers who subverted hijackers aboard United Airlines Flight 93, which crashed in a Pennsylvania field.
A sign bearing the phrase also served as a reminder to workers of their self-imposed deadline for finishing the Pentagon reconstruction by today. In the weeks after the attack, a knoll across from the Pentagon became a living memorial where the public left banners, flags, flowers and notes of sympathy and encouragement.