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Backgrounder: Pentagon Memorial
U.S. President George W. Bush and other Americans around the nation marked the seventh anniversary of the Sept. 11 terror attacks Thursday by observing a moment of silence and dedicating a memorial at the Pentagon.
The silence marks the exact time 8:46 a.m. (1246 GMT) when the first hijacked plane hit the World Trade Center in New York.
The White House ceremony was held on the South Lawn where Bush joined hundreds of other people to observe a moment of silence.
Those present included his wife, Laura, and Vice President Dick Cheney and his wife, Lynne, leaders of Congress, Cabinet members, military personnel and White House staff.
Across the Potomac River, a memorial will be formally dedicated to the 184 victims killed on Sept. 11, 2001, when a hijacked plane hit the Pentagon.
In New York, Mayor Michael Bloomberg opened Thursday's memorial event at the Ground Zero.
Services are also being held in Shanksville in the U.S. state of Pennsylvania where one of the hijacked planes crashed. About 200 people attended the ceremony there.
FIRST PERMANENT MEMORIAL
The Sept. 11 terrorist attacks "changed our world forever," Bush said when he dedicated the Pentagon Memorial at a ceremony at the Pentagon later in the day.
It is the country's first permanent memorial for 9/11 victims.
"The years that followed have seen justice delivered to evil men and battles fought in distant lands, but each year on this day our thoughts return to this place," Bush said.
"Here we remember those who died," he added.
Former Defense Secretary Donald Rumsfeld and his successor Robert Gates, as well as Michael Mullen, chairman of the Joint Chiefs of Staff, joined the president near the podium.
Tens of thousands, including the victims' families, gathered on the grounds of the Pentagon for the dedication of the memorial.
"Today as we dedicate this memorial, we also dedicate ourselves to never forget what happened here, and we make a solemn pledge to never again let this happen in America," said Deputy Defense Secretary Gordon England.
"God bless the fallen, their families and all who sacrifice for freedom and liberty," England said.
Designed by two young architects who experienced the horrific day in New York, the 22-million-U.S.-dollar memorial is composed of 184 benches, each with a name of a victim and illuminated by lighted reflection pools below.
The field of 0.77 hectares is organized as a timeline of the victims' ages, spanning from Dana Falkenberg, 3 years old, to John D. Yamnicky, 71.
TAKE A DAY OFF THE POLITICS
Senators Barack Obama and John McCain, the Democratic and Republican nominees in November's election, will appear together at the Ground Zero in the afternoon to lay wreathes in honor of the victims.
The rivals promised to take a day off the politics.
In a joint statement from the campaigns announcing their decision to visit the Ground Zero together, the two men vowed to come together "as Americans" and suspend their political campaigns for 24 hours.
"We will put aside politics and come together to renew that unity, to honor the memory of each and every American who died, and to grieve with the families and friends who lost loved ones," the statement said.
Their appearance is to be followed by another in the evening at a Columbia University forum to discuss their views on public service.
On Sept. 11, 2001, nearly 3,000 people died when terrorists crashed hijacked airplanes into the World Trade Center in New York City, the Pentagon in Arlington in the U.S. state of Virgini, and a field in Shanksville.