At 8:46 am EDT on Thursday, thousands gathered at 'Ground Zero' in lower Manhattan fell silent for a minute as they remembered 2,792 people who died in the worst terrorist strike in US history.
On September 11, 2001 the first hijacker airliner had slammed into New York's World Trade Center at 8:46 am.
President George W Bush also marked the minute of silence and prayer at a ceremony on the White House lawn in Washington.
In a brief address at 'Ground Zero', New York Mayor Michael Bloomberg spoke of the city's sense of mourning, mixed with pride and the resolve to move forward.
"Our faces and hopes turn towards the future," Bloomberg said. "In keeping with this the children who lost loved ones will lead our ceremonies. It is in them that the spirit of New York lives, carrying both our deepest memories and the bright promise of tomorrow."
After the minute's silence, 200 children who lost family members in the attack began reading the names of all those who died.
Across New York, there were quiet reminders of the anniversary on nearly every corner, with the red, white and blue of the American flag omnipresent, pasted in apartment windows or fluttering outside office buildings and shops.
President George W Bush began what he called a 'sad day' by simply standing with head bowed for a short while on the South Lawn of the White House -- a silence that was more eloquent than any words -- before going to church.
After attending the church service, Bush said: "Today, our nation remembers. We remember a sad and terrible day, September the 11th, 2001.
"We remember lives lost. We remember the heroic deeds. We remember the compassion and the decency of our fellow citizens on that terrible day."
In Washington, the chief ceremonies were at the Arlington National Cemetery, where members of the armed forces are buried.
Speakers at Arlington included the Chairman of the Joint Chiefs of Staff and Defence Secretary Donald Rumsfeld, who was in the building not far from the site of the hit on that fateful day.
Rumsfeld said that those who died on 9/11 were as surely a part of the arsenal defending democracy as any heroes in Afghanistan and Iraq.
"Without such patriots," he said, "freedom cannot exist."
"Freedom," said Rumsfeld, "is the birthright of every American. It is also the birthright of every person, for freedom is a gift of God given to all but denied to many by tyrants and dictators who place their own power above both human dignity and even human life."
On the eve of 9/11 Bush reaffirmed his doctrine that anyone who aids terrorists is also a terrorist and must be dealt with accordingly. He said, "We have made clear the doctrine which says, if you harbour a terrorist, if you feed a terrorist, if you hide a terrorist, you are as guilty as the as a terrorist. We are holding regimes accountable for harbouring and supporting terror."
In a jarring note, some tried to turn patriotism into anti-immigrant sentiment. Some members of an organisation called '9/11 Families for a Secure America' warned that unless immigration rules are tightened, there will be more 9/11s.
This was a reference to the fact that some of the hijackers had been issued visas and other suspected terrorists caught in the US since have turned out to be new immigrants.
Agencies
