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In questioning Democratic vice presidential candidate Tim Walz’s military record, Republicans are dusting off a political playbook they last used successfully exactly 20 years ago.

There’s even a name for it: swift boating.

The term — which has since made its way into dictionaries — refers to an unfair or untrue political attack. It gets its name from a Vietnam War veterans’ group’s smear campaign against John Kerry during his 2004 presidential bid.

Long before Kerry represented Massachusetts in the U.S. Senate, he served as a Naval officer during the Vietnam War. He spent four months of 1969 in Vietnam in charge of a type of patrol craft called a swift boat, leaving with multiple combat medals including three Purple Hearts.

Back home, as the war dragged on, Kerry emerged as a leading anti-war activist. In 1971, as the spokesperson for Vietnam Veterans Against the War, he spoke critically and graphically about the war in now-famous testimony before the Senate Foreign Relations Committee.

“He was an anti-war activist as well as a veteran, and that combination was a big deal,” says Derek Buckaloo, a professor of American history at Coe College in Iowa who specializes in the Vietnam War and its aftereffects.

Decades later, against the still-fresh backdrop of the Sept. 11 attacks and the U.S. invasion of Iraq, Kerry’s military heroism was a major selling point of his 2004 presidential campaign. Even his nomination acceptance speech began with the line: “I’m John Kerry, and I’m reporting for duty.”

Democrats hoped that Kerry’s status as a decorated veteran might protect him from Republicans’ accusations that the party was soft on defense, as Buckaloo explains.

“Terry McAuliffe, the head of the Democratic Party at the time, famously said that Kerry’s ‘chest full of medals’ would defend him from these sorts of attacks,” Buckaloo says. “It did not work out that way, largely because of the activities of a group called Swift Boat Veterans for Truth.”

What happened in 2004

Swift Boat Veterans for Truth was a 527 political organization that formed solely out of opposition to Kerry’s campaign.

As an independent advocacy group, it was legally permitted to fundraise and spend without limits as long as it didn’t coordinate with a presidential campaign. In other words, it was not technically affiliated with Kerry’s Republican challenger, incumbent President George W. Bush, though it didn’t hurt his chances.

“The Bush administration kept them at arm’s length, but certainly didn’t get in their way,” Buckaloo says. “And they raised tens of millions of dollars and spent those on a series of attack ads against Kerry that basically went right at his claim that being a veteran made him trustworthy, by suggesting he lied about his record.”

The group financed a book (titled Unfit for Command) and several television ads, which featured veterans casting doubt on Kerry’s heroism in Vietnam and criticizing what they considered his betrayal as an anti-war activist. The schism reflected larger cultural divides over how Americans felt about the Vietnam War in its wake, Buckaloo says.

Their accusations are widely understood to be false. Military records (released by Kerry’s campaign) backed up his combat claims. And while most of the swift boat veterans who spoke out against Kerry did not serve with him directly, the ones who did publicly supported his version of events.

In a 2018 Fresh Air interview, Kerry said his critics “just made things up … left, right and center,” and that the proof his campaign offered was no match for their “alternative facts.”

“The problem was that the right wing got behind this with major funding from some of the very same names who are doing major right-wing funding in the country today,” Kerry said. “And they started to pick up on these alternative facts and pushed them out there in the context of … television advertisements.”

The ads themselves became the story, in what Buckaloo describes as an example of pre-social media virality.

Sean Hannity of the relatively young network Fox News debuted the first ad the day before it even hit airwaves in August. Before long, TV ads originally meant for a handful of swing states were getting picked up by national talk radio hosts like Rush Limbaugh and eventually covered by the mainstream media.

The swift boating undercut Kerry’s momentum coming out of the Democratic National Convention, and turned one of his greatest strengths into a liability, Buckaloo says.

“[It] ultimately set up a situation where Kerry had to kind of run away from his status as a veteran and try not to talk about the war when, in fact, he was running against George W. Bush and Dick Cheney, two men who, famously, for various reasons, did not serve in Vietnam while he had,” he adds.

The Kerry campaign was relatively slow to respond in that initial period — a move Buckaloo says was likely meant to avoid amplifying the story but is now widely considered a misstep — and largely avoided the subject from that point on. The ads became one of the most enduring images of the 2004 election, which Kerry ultimately lost.

What’s similar — and different — this time around

While claims about a candidate’s military record — or lack thereof — continue to figure into politics, the era of swift boating had seemingly faded into memory until this week.

After Walz spoke about carrying “weapons of war” in a speech calling for gun control, Republican vice presidential candidate JD Vance publicly questioned whether his newly-minted opponent — a 24-year veteran of the National Guard — ever went to war.

Both vice presidential nominees are military veterans who never saw combat, running under presidential candidates who never served. Walz has faced questions over the years about the timing of his retirement, months before his unit mobilized to Iraq.

But this week’s “stolen valor” attack goes much farther, and directly echoes the swift boat approach of 2004. In fact, the same Republican operative has had a hand in both: Trump campaign co-manager Chris LaCivita was the chief strategist for Swift Boat Veterans for Truth.

“Birds of a feather will be tarred together,” LaCivita said, of Kerry and Walz, in a recent interview with RealClearPolitics.

But Buckaloo cautions that it’s not clear whether the line of attack will work as well in 2024 as it did in 2004 — after all, there are some key differences between the two cases.

Firstly: The context is very different. In 2004, Bush and Kerry were running to be wartime presidents, at a time when the nation was reeling from 9/11 and sending hundreds of thousands of troops overseas.

While foreign policy — and particularly the wars unfolding in Ukraine and Gaza — remains a key issue in the 2024 election, Buckaloo says the amount and nature of U.S. involvement in those conflicts aren’t comparable.

Secondly, Walz is not the presidential nominee, so he’s unlikely to attract the same level of scrutiny as Kerry did. Even former President Donald Trump himself, the Republican presidential nominee, has said publicly that the vice president “in terms of the election, does not have any impact.”

Plus, there’s the question of the source. Whereas the 2004 attacks were leveled by a now-defunct independent organization, today’s accusations against Walz are coming directly from the Trump campaign.

“That implicates the Republicans in the attack in a way that in 2004, they could kind of say, ‘Well, it’s not us and we’re not doing this,’ ’’ Buckaloo says. “But they are doing it in 2024 … in a context where plenty of Americans have questions about Trump and Vance as messengers or truth-tellers that might problematize this as well.”

And, Buckaloo says, Democrats have been through 2004 once before. He doesn’t think the party is likely to ignore Vance’s attacks.

“They realize that you can’t just let these things lie, that you’ve got to respond to them and say: ‘This is unfair, this is scurrilous. This is, to use a word that Tim Walz uses, weird,’ ” he adds.

Time will tell if that works.