"I had a choice," he says of the decision to invade Iraq and force Saddam Hussein from power.
"Do I take the word of a madman, forget the lessons of September the 11th, or take action to defend America?" Bush asks his audience. "Given that choice, I will defend America every time."
The bloody postwar insurgency in Iraq, which the president recently acknowledged he had failed to anticipate fully, has long been regarded as one of the biggest potential obstacles to another Bush term. But with less than two months to go until Election Day, the situation in Iraq is posing a sharply reduced threat to the president's re-election chances.
Today, more voters say they trust Bush, rather than Sen. John Kerry, to manage the conflict in Iraq, reviving a Bush advantage that his Democratic challenger had neutralized earlier this summer. That shift reflects several factors, including the way Republicans have effectively put Kerry on the defensive over Iraq, a difficult issue for the senator because of his shifting statements and positions over the past two years.
But the heart of Bush's success in blunting the risks that the Iraq violence poses to his re-election chances has been a relentless effort to tie the war directly to the Sept. 11 attacks.
Recent public opinion surveys show the country roughly split over Bush's handling of the situation in Iraq. But among independents, the key swing-voter group, 50 percent disapprove of his handling of the war and only 40 percent approve, according to a recent CBS News poll.
"To say that the war at this point hasn't hurt Bush probably oversimplifies matters. It's hurt him, but not as much as it might have," said Adam Clymer, political director of the University of Pennsylvania's National Annenberg Election Survey. "And that's because he has fairly successfully connected it up to terrorism, al-Qaida and Sept. 11, and because Kerry has not managed to establish himself as a real alternative."
Last week's Republican convention, which helped lift Bush to a clear lead in the presidential contest for the first time, was devoted in large measure to reviving memories of Sept. 11 in advance of today's third anniversary. Bush plans to mark the occasion by attending a religious service of remembrance in Washington, by observing a moment of silence at the White House and focusing his weekly radio address on the anniversary. Kerry will attend a commemorative event in Boston.
"One success of the convention is that it helped drive up the number of people focusing on terrorism and national security as an issue," said Republican pollster Bill McInturff. The president's biggest advantage over his Democratic rival has consistently come when voters are asked which man would do a better job of dealing with terrorism over the next four years.
By blurring the distinction between Sept. 11 and Iraq, the president is attempting to insulate himself from any political damage from the war by tying it to his greatest strength.
"Sept. 11 was the defining moment when Bush not only solidified his place in history but also bonded with the American people," said Democratic strategist Donna Brazile, who managed Al Gore's presidential campaign in 2000. "For voters who are still unsure about John Kerry, it reminds them that it was George Bush who gave them comfort and stood strong."
Kerry and the Democrats have to do a better job of "calling Bush on the carpet" for offering shifting justifications for the war, she added. "If not, Bush will effectively have been able to change the story."
As he barnstorms the country, Bush weaves the invasion of Iraq into the broader fabric of America's response to Sept. 11. Other Republicans are as relentless in drawing a connection.
"It is one and the same conflict," House Republican leader Tom DeLay of Texas said during debate in Congress this week over a resolution marking the 9/11 anniversary.
The bipartisan 9/11 Commission, led by former Gov. Thomas Kean and former Rep. Lee Hamilton, said in its report this summer that it found no evidence of a "collaborative, operational relationship" between Hussein and al-Qaida.
Still, a large number of Americans continue to tell pollsters they believe Hussein was directly involved in the 9/11 attacks. Though the number has fallen somewhat, roughly 40 percent of the public believes that.
Critics credit a masterful public relations campaign by the Bush administration.
Vice President Dick Cheney has repeatedly suggested that Hussein may have a connection to the 9/11 plot. In a speech this week, Cheney said the Iraqi dictator "provided safe harbor and sanctuary" to al-Qaida. The day before, he said that "the danger is that we'll get hit again" by terrorists if voters make "the wrong choice" in November.
The Kerry campaign, in a statement yesterday, attacked what it called the Bush administration's efforts to "hype" a non-existent connection between 9/11 and Hussein.
Political scientists see a more complex picture.
"The Bush administration clearly aimed to link Saddam Hussein to Osama bin Laden and the war on terrorism," wrote Scott L. Althus of the University of Illinois-Champaign and Devon M. Largio in a forthcoming article in the journal PS: Political Science and Politics.
In doing so, the administration "played into a favorable climate of public opinion," they conclude. "The mistaken belief that Saddam Hussein was responsible for the 9/11 attacks was already widespread among Americans long before President Bush began publicly linking Saddam Hussein with the war on Terrorism."
Karlyn Bowman, a public opinion analyst at the American Enterprise Institute, said the public's willingness to blame Hussein for Sept. 11 can be traced to the 1991 Gulf War.
Similarly, Bush has not been hurt significantly by the failure to find weapons of mass destruction in Iraq, one of the main rationales for the war. Though none have been found, and former U.N. inspector David Kay has said they don't exist, many, if not most, Americans still believe they do, polls show.
Kerry has complicated his efforts to challenge Bush's credibility on Iraq with his own positions on the war. Knowing what he does now, he said last month, he still would have voted to authorize the use of force.
University of New Orleans historian Douglas Brinkley, author of a recent admiring book about Kerry's military service in Vietnam, believes most Americans "now realize that Iraq is a secondary theater" in the anti-terror war "and wasn't necessary."
At the same time, the way the issue is playing out reinforces Bush's effort to project an image of strength and portray Kerry as correspondingly weak.
"If a rattlesnake came in your bedroom, people think if George Bush was there, he would shoot it dead and ask questions later," said Brinkley, "while Kerry would take a stick and try to relocate it."