After making his service in Vietnam the centerpiece of his presidential bid, Sen. John F. Kerry now finds himself defending his role as a protester of the war -- the chapter of his biography that first gained him prominence but which he has discussed infrequently this year.
The new focus on the antiwar part of Kerry's past is the latest twist in a more than 30-year evolution of the role his actions during the Vietnam era have played in his political life.
Kerry used his leadership in the Vietnam protest movement as a springboard into politics, running as an antiwar candidate in his first campaign in Massachusetts -- a race for the U.S. House that he lost. He also distanced himself from his military career at least once in his next five campaigns, all of which he won.
But his involvement in the peace movement receded as a key element of his political resume, as the nation's attitudes toward the Vietnam War changed.
As a presidential candidate, the Democrat has often surrounded himself with former crewmates who testify to his courage in battle as a Navy lieutenant.
But in its latest salvo against him, the group Swift Boat Veterans for Truth plans to begin running a television commercial this week that features images of Kerry testifying in front of the Senate Foreign Relations Committee in 1971, detailing atrocities some soldiers had said they committed in Vietnam.
As a leader of Vietnam Veterans Against the War, Kerry, then 27, drew national fame with his famous plea before the Senate committee, "How do you ask a man to be the last man to die for a mistake?"
Aides say Kerry will not back away from his protest years, even as the Swift boat group tries to use them against him. "John Kerry and others who marched with him and stood against the war when so many Americans had died were very proud of their efforts," campaign advisor Tad Devine said.
But throughout his White House campaign, Kerry for the most part has mentioned his antiwar activities obliquely. Instead, he has emphasized his command of a Swift boat on the Mekong Delta and his five combat medals as credentials for serving as commander in chief. Kerry's record also serves as a contrast to President Bush's stateside service in the Texas Air Guard while the Vietnam War raged.
This is the first time in his lengthy political career that the Massachusetts senator has made his military record a central theme.
Kerry "learned that the use of his military service was a double-edged sword. Most of the time he tempered it," said University of Massachusetts political scientist Lou DiNatale. "I don't think Kerry's record as a veteran would in any way be at the front end of this campaign if we weren't in Iraq."
Kerry began his political career by seeking an open congressional seat in Massachusetts' 5th District. The district's population centers were filled with conservative neighborhoods where many residents looked unkindly on the 28-year-old candidate who had been tagged a carpetbagger.
His combat medals should have appealed to voters in these neighborhoods. But he focused on his opposition to the war in Vietnam because he was passionate about the issue and thought he brought a persuasive voice to the national discussion.
As the election neared, a local newspaper, the Lowell Sun, ran editorials that questioned Kerry's patriotism and his fitness for office because of his protest activities. Kerry and his campaign did little to respond.
"We never really overtly talked about John being a hero in Vietnam," said Dan Payne, a longtime Kerry political aide. "We just assumed that people probably knew it.... We clearly missed the boat on that."
After losing the race, Kerry became a prosecutor and then a private attorney. When he emerged from self-imposed political exile to run for lieutenant governor in 1982, he wouldn't even allow a picture of him in uniform to be used in campaign literature and shied away from mention of his status as a veteran, Payne said.
"He didn't want to go back to it again," Payne said, referring to Kerry's war record. "He hadn't worked it out in his own mind whether it was a net plus or minus."
Kerry won the race and then two years later sought an open Senate seat. The main issue during the Democratic primary between two liberal candidates squaring off in a liberal state was the depth of their support for a freeze on nuclear weapon production.
But Kerry did poll voters to see if they knew which of the primary candidates was a veteran; they did not. So he ran an ad that showed him walking along the Vietnam Veterans Memorial in Washington and talking about "not sending another generation off to die for a misguided war," said Payne. It was a careful effort to meld both sides of his Vietnam experience.