9/11 commemorations: US attention turns to Ground Zero on anniversary of al-Qa'ida attacks

President Barack Obama leads nation in moment of silence, as commemoration ceremonies take place in New York, the Pentagon and the Flight 93 memorial in Pennsylvania

America paused for a moment of reflection today, as loved ones and relatives of the victims killed in the 9/11 terrorist attacks gathered for New York’s Commemoration Ceremony.

A national moment of silence was led by President Barack Obama, who took a step back from the ongoing international Syrian crisis to walk out onto the White House South Lawn with his family and senior staff.

On the 12th anniversary of the day hijacked planes crashed into the World Trade Center, wreaths were laid at the 2-year-old Ground Zero memorial plaza, and relatives recited the names of the nearly 3,000 people who died.

In keeping with a decision made prior to last year’s event, there were no politicians speaking at the New York ceremony, which included a tribute parade of firefighters and celebrities riding motorcycles from a Manhattan fire station to the site of the old Twin Towers.

It is expected to be the last anniversary ceremony before the opening of an official 9/11 museum at Ground Zero, scheduled for next spring.

And it occurred alongside events at the Pentagon – attended by Mr Obama and his family – and at the Flight 93 National Memorial in Shanksville, at the site in Pennsylvania where the third plane hijacked 12 years ago crash-landed.

Click here to see pictures of the Ground Zero commemorations through the years

Laying a wreath at the Pentagon 9/11 memorial, Mr Obama said: “Let us have the strength to face the threats that endure, different though they may be from 12 years ago, so that as long as there are those who would strike our citizens, we will stand vigilant and defend our nation.

“Let us have the wisdom to know that, while force is at times necessary, force alone cannot build the world we seek.”

Last night the commemorations were previewed by the Tribute of Light, with the New York skyline lit up by powerful beams forming ghostly outlines where the towers used to stand.

The artwork, consisting of 88 searchlights, has become a regular fixture in remembering the attacks after it was initially set up as a temporary installation 10 years ago.

Around the world people have donated money, offered tributes and pledged to do good deeds to mark the anniversary, designated a National Day of Service and Remembrance in the US.

Website such as www.tributewtc.org and www.911memorial.org carried messages of support for the families of those who died, and on Twitter the public joined together in mourning under the collective tags of #september11 and #NeverForget.

In London a charity event was held at City brokerage firm BGC Partners, where the Duke of Cambridge, Prince Harry and celebrities including singer Rod Stewart and actor Idris Elba attended to raise money in memory of those who died.

BGC lost 658 employees in the attack on the World Trade Center 12 years ago, and its annual Charity Day, now in its ninth year, has so far raised more than $89 million.

While, tributes aside, the rest of the world will more or less go on with business as usual, back in the US there was a conscious effort from most to keep today’s focus on commemorations.

Many children in the US will not have been born when the attacks happened, and as the memorial organizers expect to take primary responsibility for the ceremony next year, they say they plan to continue concentrating the event on victims' loved ones, even as the forthcoming museum creates a new, broader framework for remembering 9/11.

“As things evolve in the future, the focus on the remembrance is going to stay sacrosanct,” memorial President Joe Daniels said.