NEW YORK Moments of silence were observed in New York City Sunday on the tenth anniversary of the terror attacks that destroyed the World Trade Center and killed nearly 3,000 people.
At a ceremony this afternoon in Shanksville, Pa., the passengers and crew of United 93 were remembered for their selfless heroism, at the newly-dedicated Flight 93 Memorial - erected in a field where the hijacked airliner was brought down.
President Obama and first lady Michelle Obama paid tribute to the 40 passengers and crew members, helping place a wreath at the marbled Wall of Names memorializing those who crashed at Shanksville after fighting back against the hijackers aboard their plane.
And at a ceremony at the Pentagon, the president laid a wreath at the 9/11 memorial built in the path of the ill-fated American Airlines Flight 77.
At a morning ceremony at the Pentagon, which was heavily damaged in the 9/11 attacks, Vice President Joe Biden paid tribute to U.S. service members: "Never before in our history has America asked so much over such a sustained period of an all-volunteer force."
In New York City, where relatives and dignitaries gathered to commemorate the 10th anniversary of the attacks and to dedicate the 9/11 Memorial at ground zero, Mayor Michael Bloomberg said, "Ten years have passed since a perfect blue sky morning turned into the blackest of nights. Since then, we have lived in sunshine, and in shadow.
"And although we can never 'unsee' what happened here ... we can also see that children who lost their parents have grown into young adults, grandchildren have been born, and good works and public service have taken root to honor those we loved and lost."
Noting that the words of writers and poets have been used to express what is in our hearts, Bloomberg recalled Shakespeare in saying, "Let us not measure our sorrow by their worth, for then it will have no end."
President Barack Obama stood before the white oak trees of the new Sept. 11 memorial and read Psalm 46 from the Bible, after a moment of silence at 8:46 a.m., when the first jetliner slammed into the World Trade Center's north tower a decade ago.
"God is our refuge and strength," the psalm said. "He dwells in his city, does marvelous things and says, be still and know that I am God."
President George W. Bush read the words of another president, Abraham Lincoln, whom he said "understood the cost of sacrifice, and reached out to console those in sorrow as best he could."
Reading a letter written to a mother who'd lost five sons in the Civil War, Mr. Bush said, "I pray that our Heavenly Father may assuage the anguish of your bereavement, and leave you only the cherished memory of the loved and lost, and the solemn pride that must be yours to have laid so costly a sacrifice upon the altar of freedom."
Tales of heroism and sacrifice were told, from the police officers who gave their lives while saving others, to the fathers and mothers who were missing from the lives of their children.
Peter Negron, whose father worked on the 88th floor of the World Trade Center, recalled that he's tried to teach his younger brother all the things his father had taught him, like riding a bike. "I wish my dad had been there - to teach me how to drive, ask a girl out on a date, and see me graduate from high school, and a hundred other things I can't even begin to name."
Negron said he wants to become a forensic scientist. "I hope that I can make my father proud of the young men my brother and I have become. "
Earlier, Mr. Obama and Mr. Bush bowed their heads at the trade center site and ran their hands over the bronze-etched names of the victims of the attack.
The presidents were joined by their wives as they walked up to one of the two reflecting pools built over the towers' footprints, part of a Sept. 11 memorial that was to open later in the day for relatives of the victims.
The president and former president later embraced family members and talked to dignitaries, including Bloomberg, former Mayor Rudolph Giuliani and the governors of New York and New Jersey.
As the sun rose at the site Sunday, an American flag fluttered over six stories of the rising 1 World Trade Center. The sky was clear blue with scattered white clouds and a light breeze, not unlike the Tuesday morning 10 years ago.
Remembrances around the nation and world were planned to mark a decade of longing for loved ones lost in the attacks. Of sending sons, daughters, fathers and mothers off to war in foreign lands. Of redefining what safety means and worrying about another 9/11 or something even worse.
Ten years has arrived. And with it, memories. Of that September morning, when terrorists crashed hijacked planes into the World Trade Center and the Pentagon, and a fourth plane crashed into a field in rural western Pennsylvania. Of heroism and Samaritans and unthinkable fear. And of nearly 3,000 killed at the hands of a global terror network led by Osama bin Laden, himself now dead.
People across America planned to gather to pray at cathedrals in their greatest cities and to lay roses before fire stations in their smallest towns. Around the world, many others will do something similar because so much changed for them on that day, too.
Bells will toll. Americans will see new memorials in lower Manhattan, rural Pennsylvania and elsewhere, symbols of a resolve to remember and rebuild.
But much of the weight of this year's ceremonies lies in what will largely go unspoken. There's the anniversary's role in prompting Americans to consider how the attacks affected them and the larger world and the continuing struggle to understand 9/11's place in the lore of the nation.
"A lot's going on in the background," said Ken Foote, author of "Shadowed Ground: America's Landscapes of Violence and Tragedy," examining the role that veneration of sites of death and disaster plays in modern life. "These anniversaries are particularly critical in figuring out what story to tell, in figuring out what this all means. It forces people to figure out what happened to us."
On Saturday in rural western Pennsylvania, more than 4,000 people began to tell the story again.
At the dedication of the Flight 93 National Memorial near the town of Shanksville, Bush and former President Bill Clinton and Vice President Joe Biden joined the families of the 40 passengers and crew aboard the jet who fought back against their hijackers.
"The moment America's democracy was under attack our citizens defied their captors by holding a vote," Bush said. Their choice cost them their lives.
The passengers and crew gave "the entire country an incalculable gift: They saved the Capitol from attack," an untold amount of lives and denied al Qaeda the symbolic victory of "smashing the center of American government," Clinton said.
They were "ordinary people given no time at all to decide and they did the right thing," he said.
"And 2,500 years from now, I hope and pray to God that people will still remember this."
The Pennsylvania memorial park is years from completion. But the dedication and a service to mark the 10th anniversary of the attacks are critical milestones, said Sally Ware, one of the volunteer "ambassadors" who has worked as a guide at the site since the disaster.
Ware, whose home was rocked when the jet crashed two miles away, recalled how hundreds of people flocked to the site in the days afterward to leave their own mementos and memorials. She began volunteering after finding one along the roadside a red rose placed atop a flight attendant's uniform.
"It really bothered me. I thought someone has to take care of this," said Ware, whose daughter is a flight attendant.