President Barack Obama observed a moment of silence at the White House Sunday at 8:46 a.m., when the first of the four hijacked planes slammed into the World Trade Center, before speaking at a ceremony at the Pentagon, the U.S. military headquarters, honoring those killed in the attacks.
"We remember and we will never forget the nearly 3,000 beautiful lives taken from us so cruelly," Obama said. "We wonder how their lives might have unfolded, how their dreams might have taken shape."
As they have been in past 9/11 commemorations in New York, the names of the 2,983 killed that horrifying day were read slowly by their relatives as music played in the background. As daylight ends Sunday in New York, spotlights will project two giant beams of light into the sky to represent the fallen twin towers of the World Trade Center.
A September 11 Museum has been erected on the New York site where the World Trade Center once stood, housing artifacts and photographs connected to the attack.
At the Pentagon, the 184 people who died on September 11, 2001 are honored with 184 benches over pools of water. A huge American flag was draped from the roof of the headquarters of the country's Defense Department on the side of the building where the attack occurred.