In the early days of the general-election campaign, Democrat John F. Kerry has mounted a strong effort to erode President Bush's advantage on national security. But on the defining issue of war in Iraq, his shots have appeared oblique at best.

The war received relatively short shrift at last week's Democratic National Convention -- Kerry devoted only six sentences to Iraq policy in his 45-minute acceptance speech -- and on the stump he seldom discusses his plans for bringing the U.S. occupation to a close and stabilizing the country.

Kerry has strongly criticized the Bush administration's competence in handling the war, principally its failure to enlist other nations to its cause in Iraq. But he has not questioned the basic tenets of the policy, nor has he outlined a course of action substantially different from the one Bush is pursuing to shore up the interim government and prepare for national elections. While he has said he would substantially cut troop strength in Iraq by the end of his first term, he has not provided details on how.

And when Kerry does raise questions about Bush's Iraq policies, they seem to be suggestive, not pointed. Surrounding the nominee on stage in Boston were his former Swift boat crewmates in Vietnam, the subtext being that Kerry knew all about the horrors of war -- unlike Bush, who served stateside in the National Guard -- and is better capable to extricate the United States from that troubled nation.

"I defended this country as a young man," Kerry told the convention, "and I will defend it as president."

Kerry's careful approach on Iraq is born from something of necessity. As senator, after all, he voted to give Bush authorization to conduct the war. But Kerry campaign officials also say the candidate has chosen not to address Iraq in detail at this point because of their desire to introduce the Massachusetts senator to the American public, over a range of domestic and international themes. Polls have suggested voters do not know Kerry well.

"The acceptance speech was clearly intended to be thematic," said Richard C. Holbrooke, a senior foreign policy adviser to Kerry. "It was not just about Iraq."

Holbrooke and other Kerry advisers point out that Kerry has spoken about Iraq in detail before and will do so again. In a July 4 op-ed article in The Washington Post, for instance, Kerry said he would bring in allies to share more of the burden by giving them access to reconstruction contracts and helping to repair Iraq's oil industry, if they forgave Iraq's debt and helped pay reconstruction costs. He also called for a conference with Iraq's neighbors and a potential deployment of NATO forces in Iraq.

Indeed, his advisers say, it is Bush who has followed Kerry's calls for more international support and a United Nations imprimatur for U.S. policies in Iraq. "Kerry's been the consistent one, and Bush is the one who has changed his position," Holbrooke said.

Bush and his surrogates are working hard to use Iraq to frame Kerry as a flip-flopper, seizing repeatedly on his opposition last year to an $87 billion spending measure to support the troops and provide reconstruction money for Iraq -- a Senate vote cast in the midst of the Democratic presidential primary contests when antiwar candidate Howard Dean was riding high.

Kerry has said he voted against the measure because it was not funded -- he supported the request if tax cuts for the wealthy were trimmed to pay for it -- but one of his closest advisers, Sen. Joseph R. Biden Jr. (D-Del.), has told other Democrats that he begged Kerry not to vote against the $87 billion.

Bush campaign spokesman Terry Holt said Kerry's inability to "talk straight about that vote on Iraq" will haunt him. "He voted for the war and voted against funding for Iraq," Holt said. "As long as you look at John Kerry through a gauzy haze of images and rhetoric, they have a chance. You have to look at his record."

In Bush's revamped stump speech Friday, he drew particular glee in focusing on the vote over the $87 billion. "He tried to explain his vote by saying: I actually did vote for the $87 billion before I voted against it. End quote," Bush said to laughter. "He's got a different explanation now. One time he said he was proud he voted against the funding, then he said that the whole thing was a complicated matter." Bush then added: "There is nothing complicated about supporting our troops in combat!"

There is some precedent for Kerry's approach on Iraq. In 1968, Republican challenger Richard M. Nixon took virtually the same tack as Kerry when he accepted the GOP nomination. Despite mass protests against the Vietnam War, Nixon only briefly touched on the conflict in his speech, criticizing the Democrats for incompetence in conducting the war, pledging to bring it to an "honorable end," and calling on allies to bear more of "the burden of defending peace and freedom around this world." Nixon, who had been Dwight D. Eisenhower's vice president, also said he had experience in ending wars, pointing to the conclusion of the Korean War during the Eisenhower administration.

The Vietnam War did not end for another seven years.

Much like Nixon, Democrats plan to use Bush's handling of war -- particularly what they call poor planning, the violence and the failure to find weapons of mass destruction that followed the lightning victory by U.S. and British forces -- as a broader metaphor for his competence to continue as president. While Kerry did not speak much about Iraq specifically, his speech was sprinkled with indirect references to the protracted struggle the United States faces in Iraq.

"The American people know that whatever you thought about going into the war, that there could have been a better way to go about executing it," said House Minority Leader Nancy Pelosi (D-Calif.). "Because of the lack of preparation and understanding as to what to expect, many more men and women have died and been wounded. . . . The administration will be held accountable for its policy."

The Bush campaign brushes aside those questions and focuses instead on the threat ousted Iraqi president Saddam Hussein might have posed to the United States before the war, implicitly contrasting Bush's certainty against Kerry's more protracted decision making. "When he [Hussein] continued to deceive the weapons inspectors, I had a decision to make: to hope for the best and to trust the word of a madman and a tyrant or remember the lessons of September the 11th and defend our country," Bush said Friday. "Given that choice, I will defend America every time."

While Republicans strongly favor Bush's decision to attack Iraq, Kerry also must energize a Democratic base that is deeply split over the war. Nine out of 10 delegates to the convention opposed the war, surveys indicated.

That balancing act was on display at the convention. Kerry's running mate, John Edwards, in his acceptance speech, said a Kerry administration would work for a stable, democratic Iraq, which he called "a real chance for freedom and peace in the Middle East." He also said Kerry would bring NATO forces into Iraq and win debt relief for Iraq from balking allies.

But unlike Edwards, Kerry did not say his goal was a stable, democratic Iraq. Instead, he spoke only of bringing allies into the coalition. "I know what we have to do in Iraq," Kerry said. "We need a president who has the credibility to bring our allies to our side and share the burden, reduce the cost to American taxpayers, reduce the risk to American soldiers. That's the right way to get the job done and bring our troops home."

Some experts, such as Robert Kagan of the Carnegie Endowment for International Peace, felt Kerry's language came very close to suggesting that he would pull the 140,000 U.S. troops out of Iraq. "I was a bit surprised," said Kagan, who strongly supported the invasion of Iraq but has been critical of the administration's postwar policy. "Edwards was pretty straightforward and clear about the commitment to Iraq. Kerry was far more tentative. He held out hope that he would get out."

His advisers, however, denied Kerry meant to leave that impression. "John Kerry has resisted left-wing pressure to set a date certain for withdrawal because he knows the consequences would be catastrophic," Holbrooke said. "But he believes . . . he will do better to create international support to deal with this problem."

Staff writer Charles Babington contributed to this report.