It's entirely possible that the full story of President Bush's service in the National Guard more than 30 years ago - again the subject of intense scrutiny - will never be told.
Mr. Bush insists he fulfilled his duties. But two superior officers who could corroborate his statements are no longer alive. A commanding officer says he's not sure, but cannot recall Bush showing up for duty. Records newly released by the White House show that Bush was paid for some of the days in question, but do not prove he reported for duty in Alabama.
What is certain is that most presidents running for reelection don't have to address old biographical information that had already been ploughed through during the first campaign. And certainly, analysts say, Bush's reelection will hinge more on his record of the past four years and his vision for the future than on how he spent his time in 1972 and '73.
But 2004 is vastly different from 2000. Four years ago, the nation was at peace and Bush's opponent had not seen combat in Vietnam, either. Now, national security is a central issue and Bush is likely to face a decorated Vietnam War hero in the general election.
Perhaps most important, the flap over Bush's National Guard service raises questions about the president's credibility at a time when his most valuable asset - a reputation for integrity and candor - is under siege. Questions about whether he took the nation to war under false claims that Iraq had weapons of mass destruction and about a spraling budget deficit top the list.
"One of Bush's strengths is he seems to be a straight shooter, and his ratings on integrity and honesty are still pretty good," says John Mueller, a political scientist at Ohio State University. "If you can chip away at that, that's obviously good for the Democrats. If he's been lying or Clintonizing, that would be the ultimate coup de grace. He might even lose some Republican votes that way."
So for Massachusetts Sen. John Kerry, the Democrats' likely presidential nominee, the decision by national party chair Terry McAuliffe to bring back the question of Bush's National Guard service is a two-fer. Not only does it raise questions about Bush's candor. It also invites stark comparisons between Senator Kerry's "chestful of medals" heroism in Vietnam and Bush's comfortable war-era assignment stateside, allegedly secured through family connections.
Some Kerry opponents are fighting back by reigniting discussion of Kerry's antiwar activities after his return from Vietnam. A picture of Kerry and actress Jane Fonda attending the same antiwar rally in Valley Forge, Pa., is circulating on the Internet, inflaming the passions of some veterans and giving some Republicans (though not the White House) a talking point that changes the subject away from Bush.
For Bush, if no new information surfaces about his National Guard service, the story will probably die down. And as he campaigns for reelection, he will tout his stewardship of national security post-9/11, which analysts say is likely more relevant to his pitch for four more years than his own lack of combat experience.
"He's doing his commander in chief thing, whatever the issue was with Guard service," says Professor Mueller. "It's something [the Democrats] are going to hit, and it's probably going to have some impact, but it certainly won't decide the election."
But for Kerry, the question is whether his own valorous military service eliminates Bush's election advantage as an incumbent with three years' experience as commander in chief. At the very least, Kerry's record cancels out some of Bush's advantage, analysts say. Much will also depend on events between now and election day - for example, how the public reacts to continuing US war deaths and injuries in Iraq, how the scheduled transfer of control to Iraqis proceeds, whether there is another terrorist attack on US soil.
It's still early in the election year, and most voters don't know a lot about Kerry. But polls show that early impressions are mostly positive. A Newsweek poll late in January shows 62 percent of registered voters believe Kerry has "strong qualities of leadership." Fifty-two percent of voters say they would trust him to make right decisions during an international crisis. "Early impressions are very, very important in politics," says Karlyn Bowman, a polling expert at the American Enterprise Institute. "People won't be attentive for a long time, but they get glimpses of a candidate. And if you see someone like Rassman [a man whose life Kerry saved during the war] over and over on the news, that helps define Kerry for you."
In the end, the relative import of questions about Bush's military service during the election boils down to how voters in the center of the political spectrum perceive the issue. And there are several ways to perceive the question, says Stephen Wayne, a political scientist at Georgetown University. "For some, it will be a patriotism issue, for others a credibility issue, and for others, it happened too long ago to matter," he says.