WHITE HOUSE - President Barack Obama and first lady Michelle Obama participated in observances at the White House and the Pentagon marking the 11th anniversary of the September 11, 2001 al-Qaida terrorist attacks on the United States.
As President Obama observed, the cool, bright sunny morning was a reminder of the day 11 years before when terrorists struck the United States.
The president and his wife Michelle gathered with hundreds of staff members on the White House South Lawn.
At 8:45 a.m. ET, two U.S. Marines appeared at the door underneath the White House portico, while two others presented the colors, one holding the U.S. flag, another a trumpet.
A minute later, marking the moment American Airlines Flight 11 struck the North Tower of the World Trade Center in New York City, a full Marine color guard emerged.
The Obamas stood with heads bowed, facing the National Mall, as the Marine trumpeter played taps and all held their hands to their hearts.
They then traveled the short distance to the Pentagon in Virginia where in 2001 terrorists crashed American Airlines Flight 77 into the building.
With Defense Secretary Leon Panetta, they laid a wreath at the Pentagon Memorial in honor of the 184 people who lost their lives there.
No matter how many years pass, the president said, those who died in the attacks will not be forgotten.
"It is because of their sacrifice that we have come together and dealt a crippling blow to the organization that brought evil to our shores. Al-Qaida's leadership has been devastated. Osama bin Laden will never threaten us again. Our country is safer and our people are resilient," said Obama.
Video of September 11 ceremonies in Washington and New York
Panetta said the September 11, 2001 attacks produced a new sense of unity in America.
"Out of the shock and sadness of 9/11 came a new sense of unity and resolve that this would not happen again. It inspired a fierce determination to fight back and protect our way of life. In trying to attack our strengths, the terrorists unleashed our greatest strength, the spirit and the will of Americans to fight for their country."
As on previous September 11 anniversaries, the president and his wife stopped at Arlington National Cemetery to visit an area reserved for the graves of military personnel killed in the wars in Iraq and Afghanistan.
Later in the day, Obama visited the Walter Reed National Military Medical Center to meet with wounded military personnel.