Washington ? Five years after the worst attack on U.S. soil, President Bush said Monday night 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 in a prime-time address from the Oval Office. “The war is not over – and it will not be over until either we or the extremists emerge victorious.”

Bush also staunchly defended the war in Iraq though he acknowledged that Saddam Hussein was not responsible for the 9/11 attacks that killed nearly 3,000 people.

His address came at the end of a day in which he visited New York, Pennsylvania and the Pentagon to honor victims of the attacks that rocked his presidency and thrust the United States into a costly and unfinished war against terror.

“We are now in the early hours of this struggle between tyranny and freedom,” the president said.

As for Iraq, he said Saddam’s regime, while lacking weapons of mass destruction, was a threat that posed “a risk the world could not afford to take.” At least 2,670 U.S. servicemen and women have died in Iraq, which Bush calls the central front in the war on terror.

“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.”

The nation is split over the war in Iraq and Bush’s handling of it, and Sen. Charles Schumer, D-N.Y., accused Bush of playing politics.

“This should have been an occasion to bring everyone together, and focus on the tragedy, the many we lost, and the heroism of those who embodied the American spirit,” Schumer said. “You do not commemorate the tragedy of 9/11 by politicizing it.”

Terrorism has been a potent political issue for Republicans, and they hope to capitalize on it in the upcoming elections. GOP lawmakers are anxious about holding control of both houses of Congress.

Congress has approved $432 billion for Iraq and the war on terrorism.

“The safety of America depends on the outcome of the battle in the streets of Baghdad,” the president said. He quoted bin Laden as calling Iraq “the Third World War.”

“Our nation has endured trials, and we face a difficult road ahead,” the president said. “Winning this war will require the determined efforts of a unified country. So we must put aside our differences and work together to meet the test that history has given us.”

While Bush urged resolve, the two co-chairs of the 9/11 Commission accused the Bush administration and Congress of a lack of urgency in protecting the country. About half of their 41 recommendations to better secure Americans, offered in July 2004, have become law.

“Where in the world have we been for five years?” said former Rep. Lee Hamilton, D-Ind., who was joined by his Republican counterpart, former New Jersey Gov. Tom Kean. Hamilton spoke of failures to put first responders on the same radio spectrum so they can talk to each other during an emergency – as firefighters and police officers who died in the World Trade Center could not in 2001.

Despite the political differences, dozens of lawmakers of both parties joined on the steps of the Capitol Monday to remember the attacks, singing “God Bless America” as they had five years ago.

House Democratic leader Nancy Pelosi said Monday, “Five years later, we have to continue to move forward with unity, urgency and in the spirit of international cooperation, because we are not yet fully healed and not yet as safe as we should be.”