NEW YORK -- Determined never to forget but perhaps ready to move on, the nation gently handed Sept. 11 over to history yesterday and etched its memory on a new generation.
A stark memorial took its place where twin towers once stood and the names of the lost resounded from children too young to remember terror from a decade ago.
In New York, Washington, and Pennsylvania, across the United States and the world, people carried out rituals now as familiar as they are heartbreaking: American flags unfurled at the new World Trade Center tower and the Eiffel Tower, and tears shed at the base of the Pentagon and at a base in Iraq.
Political and religious leaders urged the nation to recall the spirit of common national purpose that defined that day and its immediate aftermath.
President Obama quoted the Bible and spoke of finding strength in fear.
George W. Bush, still new to the presidency that day 10 years ago, invoked the national sacrifice of the Civil War.
It was the 10th time the nation has paused to remember a defining day.
In doing so, it closed a decade that produced two wars, deep changes in national security, shifts in everyday life -- and the death at American hands of the elusive terrorist who masterminded the attack.
"These past 10 years tell a story of resilience," Mr. Obama said last night at a memorial concert at the Kennedy Center after he visited all three attack sites.
"It will be said of us that we kept that faith; that we took a painful blow, and emerged stronger," the President said.
The anniversary took place under heightened security.
In New York and Washington especially, authorities were on alert.
Streets near the trade center were blocked. To walk within blocks of the site, people had to go through security checkpoints.
The names of the fallen -- 2,983 of them, including all the victims from the three Sept. 11 attack sites and six people who died when terrorists set off a truck bomb under the towers in 1993 -- echoed across a place utterly transformed.
In the exact site of the two towers was a stately memorial, two great, weeping waterfalls, unveiled for the first time and, at least on the first day, open only to the relatives of the victims. Around the square perimeter of each were bronze parapets, etched with names.
Some of the relatives were dressed in funereal suits and others in fire department T-shirts.
They traced the names with pencils and paper. Some left pictures or flowers, fitting the stems into the recessed lettering.
At the south tower pool, an acre in area and 30 feet deep, Mary Dwyer, of Brooklyn, remembered her sister, Lucy Fishman, who worked for Aon Corp., an insurance company that occupied seven floors near the top.
"It's the closest I'll ever get to her again," she said.
One Sept. 11 relative pronounced the memorial breathtaking.
An underground section and a museum won't open until next year, but for many of the families, the names were enough.
"It breaks me up," said David Martinez, who watched the attacks happen from his office in Manhattan and later learned he had lost a cousin and a brother, one in each tower.
At memorial services, people talked of grief and loss and war and justice.
But they also talked of moving forward.
"Every year it becomes more significant," Barbara Gorman said at a service for the Port Authority dead, which included 37 police officers, one of them her husband, Thomas. "My kids are 25, 21, 18. They understand now. It's not so much a tragedy anymore as history, the history of our country."
In the decade between then and now, children have grown.
The second-graders who were with Mr. Bush on the morning of Sept. 11, 2001, will graduate high school next spring. And children who were in the cradle or the womb on that day are old enough to read names at the anniversary, old enough to bear the full burden of their grief.
"You will always be my hero," Patricia Smith, 12, said of her mother.
Nicholas Gorki remembered his father, "who I never met because I was in my mother's belly. I love you, Father. You gave me the gift of life, and I wish you could be here to enjoy it with me."
Mr. Obama, standing behind bulletproof glass and in front of the white oak trees of the memorial, read a Bible passage after a moment of silence at 8:46 a.m., when the first jetliner slammed into the north tower 10 years ago.
The President, quoting Psalm 46, invoked the presence of God as an inspiration to endure: "Therefore, we will not fear, even though the earth be removed, and though the mountains be carried into the midst of the sea."
Mr. Obama and Mr. Bush, joined by their wives, walked up to one of the pools and put their hands to some of the names.
Mr. Bush later read from a letter that President Abraham Lincoln wrote to a mother believed to have lost five sons in the Civil War: "I pray that our heavenly father may assuage the anguish of your bereavement."
At the Pentagon, Vice President Joe Biden remembered the attack as a "declaration of war by stateless actors bent on changing our way of life." The goal: "To break us."
But, "they did not know us."
The attacks galvanized a "new generation of patriots -- the 9/11 generation," Mr. Biden said, noting that since then, nearly 3 million men and women have signed up for armed-services duty "to finish a war begun here that day."
At the end of the hour-long ceremony, service members laid wreaths at every bench in the memorial, one for each life lost.
One hundred eighty-four people died at the Pentagon.
Defense Secretary Leon Panetta paid tribute to 6,200 members of the U.S. military who have died in the Iraq and Afghan wars.
In Shanksville, Pa., a choir sang at the Flight 93 National Memorial, and a crowd of 5,000 listened to a reading of the names of 40 passengers and crew killed aboard the fourth jetliner hijacked that day.
There were also long moments of silence throughout the day.
The first was at 8:46 a.m., the time American Airlines Flight 11 struck the north tower, and again at 9:03 a.m., when United Airlines Flight 175 smashed into the other tower.
Another silence -- at Ground Zero and at the Pentagon -- came at 9:37 a.m., when American Airlines Flight 77 slammed into the nerve center of the world's most powerful military.
Another moment of silence, at 10:03 a.m., marked the crash of United Airlines Flight 93 in Shanksville, Pa. -- the plane on which passengers tried to fight back, storming the cockpit and trying to take control of the plane from the terrorists who had hijacked it.
Elsewhere it was a day not to bring life to a stop, as it was 10 years ago, but to pause and reflect.
In southwest Missouri, where 160 people died in May in the nation's deadliest tornado in six decades, New York firefighters and Ground Zero construction workers joined survivors in a tribute to the victims of Sept. 11.
The New York contingent brought a 20-by-30-foot American flag recovered a decade ago from a building near the trade center.
Survivors of a Greensburg, Kan., tornado began repairing the flag in 2008, using remnants of flags from their town.
The final stitches are being made in Joplin, Mo., and then the flag will go to the National 9/11 Memorial Museum. Missouri is the last stop on a 50-state tour to promote national unity and volunteerism.
"We're so far away from the World Trade Center," said Christy Miller, who brought her mother and two children to the Joplin tribute. "But it doesn't matter how far away you are."
The world offered gestures large and small.
The Colosseum in Rome, rarely lit up, glowed in solidarity. Pope Benedict XVI encouraged people to resist "temptation toward hatred" and focus on justice and peace.
Taps sounded in Belgium and in Bagram, Afghanistan.
In London, British Prime Minister David Cameron, Prince Charles, and U.S. Ambassador Louis Susman laid a wreath at a 9/11 memorial garden near the embassy.
Relatives of the 67 British citizens who died in the attacks read their names and placed a white rose for each on the memorial.
"To say that we understand, that we sympathize, that we hold you in our thoughts and prayers is true," Prince Charles told the guests, "but I know it's hopelessly, utterly inadequate."