Tuesday, September 12 2006 11:47 Hrs (IST) - World Time -

Washington: Five years after the worst terror attack in US history, President George W. Bush said the war against terrorism is the calling of our generation and urged Americans to put aside differences and fight to victory.

"America did not ask for this war, and every American wishes it were over," Bush said.

"The war is not over and it will not be over until either we or the extremists emerge victorious," he said.

Bush, in a televised evening address from his Oval Office in the White House, staunchly defended the war in Iraq, even though he acknowledged that deposed Iraqi President Saddam Hussein was not responsible for the Sept 11 attacks that killed nearly 3,000 people.

He said Saddam's regime, while lacking weapons of mass destruction, was a clear threat that posed a risk the world could not afford to take. At least 2,600 US servicemen and women have died in Iraq.

Whatever mistakes have been made in Iraq, the worst mistake would be to think that if we pulled out, the terrorists would leave us alone," the president said.

"They will not leave us alone. They will follow us," he said.

The address came at the end of a day in which Bush honoured the memory of the attacks that rocked his presidency and thrust the United States into a costly and unfinished war against terror.

It was a day of mourning, remembrance and resolve. Before his address, Bush visited New York, Shanksville, Pennsylvania, and the Defense Department's Pentagon headquarters to place wreaths and console relatives of the victims.