Pentagon memorial unveiled as U.S. recalls Sept 11

"Seven years ago at this hour a doomed airliner plunged from the sky, split the rock and steel of this building and changed our world forever," Bush said.

"The years that followed have seen justice delivered to evil men in battles fought in distant lands."

To the accompaniment of choral music, military members in dress uniform unveiled the 184 granite-and-steel benches in the memorial park that represent each of the victims killed by the al Qaeda attack on the Pentagon.

The ceremony was the last time that Bush, who steps down in January, will lead the nation in recalling the attacks that prompted him to declare a global war on terrorism that has defined his presidency.

"Since 9/11, our troops have taken the fight to the terrorists abroad so we do not have to face them here at home," said Bush, joined at the ceremony by former Defense Secretary Donald Rumsfeld, who was in the Pentagon during the attack.

"Thanks to the brave men and women, and all those who work to keep us safe, there has not been another attack on our soil in 2,557 days," he said to applause.