Governor Tim Walz’s military career has always been at the heart of his political career. The likely Democratic vice presidential nominee joined the National Guard at age 17 and honorably retired 24 years later.

But former President Donald Trump’s campaign has launched a series of attacks aimed at discrediting Walz’s service just as the Democratic presidential nominee, running mate Vice President Kamala Harris, is gaining ground in the polls. The attacks, led by Trump’s vice presidential nominee Senator JD Vance, claim that Walz avoided a National Guard deployment to Iraq and lied about his military record.

Walz, who denies the allegations, has been dogged by such accusations since he first ran for Congress and then for governor of Minnesota. Despite renewed attacks from Vance, himself a Marine Corps veteran, the facts about Walz’s retirement before his unit deployed, the references to his rank in the Guard and his own description of his wartime service appear much less clear.

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The Trump campaign’s claims may also lack nuance regarding the National Guard’s deployment and retirement schedules, which mean citizen-soldiers must juggle a desire to serve their country with sometimes irregular military deployments and an ambition to accomplish more in their civilian lives.

“I’m not criticizing Tim Walz’s service,” Vance said on Sunday on CNN’s “State of the Union.” “I’m criticizing the fact that he lied about his service for political reasons. I think that’s scandalous behavior.”

Vance himself was in charge of public relations for the Marine Corps for four years. His job essentially consisted of publishing press releases and photos of the service for the public. In 2005, he was deployed to Iraq for six months.

After serving in the National Guard for 24 years, Walz retired in 2005, two months before his unit received official orders to deploy to Iraq. However, it is possible that Walz knew of the impending deployment order because he held a higher rank.

At the time of his retirement, he was Command Sergeant Major of the 1st Battalion, 125th Field Artillery of the Minnesota National Guard, the highest rank in that formation.

It’s unclear when Walz made the decision to retire, and retirement paperwork often begins months in advance. National Guardsmen can retire after 20 years of service, but Walz has said he decided to reenlist rather than retire after 20 years because of the Sept. 11, 2001, terrorist attacks.

National Guardsmen must balance their civilian careers with those of their colleagues, and when Walz, who was a teacher before entering politics, retired, he was running for Congress. Rumors of deployments are frequent, especially at the height of the wars in Iraq and Afghanistan. In addition, deployments are regularly canceled or postponed.

Guardsmen are deployed on average about 50 days a year, and that doesn’t include deployments or extended training events. Soldiers in higher positions like Walz are expected to invest much more time planning training or deployments.

Walz first filed papers with the Federal Election Commission announcing that he was considering running for Congress in February 2005, according to filings available on the commission’s website and an archived statement from his campaign team.

About a month later, in March 2005, Walz issued a statement saying the National Guard had informed his unit it could deploy to Iraq “within the next two years.” Walz said in the statement that he still plans to run for Congress, but he also understands his “responsibility to not only prepare my battalion for Iraq, but to serve when called upon.”

In May 2005, at the age of 41, he officially retired from the National Guard, according to his military service records. His unit received official deployment orders in July 2005.

Walz’s unit went to Iraq in March 2006 for a 22-month deployment. According to unit casualty reports, four guardsmen died during the deployment.

In a 2009 interview with the Library of Congress as part of the veterans’ oral history project, Walz said he retired to focus “fully on running” for Congress. He added that he was concerned about balancing his campaign with the Hatch Act, a law that prohibits federal employees from engaging in political activity while on the job. The law does not apply to military personnel, although there are other laws that prohibit political activity while in uniform.

A spokesman for the Harris-Walz campaign did not respond to a request for comment Monday, including when exactly Walz submitted his resignation papers. Harris had previously defended her running mate.

“I commend everyone who has stepped forward to serve our country, and I think we all should,” Harris told reporters last week.

Republican criticism of Walz also focused on the question of whether he had embellished his service record.

In various biographies on campaign and government websites over the years, Walz has described himself as being deployed “in support” of Operation Enduring Freedom, the official name for the U.S. mission in Afghanistan from 2001 to 2014. Although the mission included operations outside Afghanistan that put most soldiers out of harm’s way, the public understands them to be purely Afghanistan operations.

Walz was part of a deployment in Italy in 2003, where his unit provided security at air bases as part of Operation Enduring Freedom. But Republicans accuse him of using the connection to Operation Enduring Freedom to imply that he was deployed to Afghanistan.

Walz himself was disgusted by this kind of criticism when it first came out during his 2006 campaign for Congress. After Walz was criticized in a letter to the editor of a local newspaper for “strongly suggesting that he had fought in Iraq or Afghanistan,” Walz himself wrote a letter rejecting the “ridiculous claim that I was misleading voters.”

“If you are unclear about my service, you could have checked my website or simply had the decency to call me and ask,” Walz wrote in the letter, which was published in the Winona Daily News, a newspaper in his congressional district. “When you dishonor one veteran, you dishonor all service members and veterans. You owe an apology to all who serve honorably.”

There There were times when others have called Walz an Afghanistan veteran, and he has not corrected them. But in several other interviews over the years, Walz has clarified that he has never been in combat or deployed to a war zone.

“I know there are certainly people who have done a lot more than I have. I know that,” Walz said in a 2018 interview with Minnesota Public Radio.

Walz joined the Nebraska Army National Guard as an infantryman in 1981, at the height of the Cold War, but later transferred to the field artillery. When he retired, he was a command sergeant major, but because he had not completed the Sergeants Major Academy – training required to retain the rank – he was reverted to the rank of master sergeant upon his retirement.

Even references to Walz being a sergeant major led to criticism and political attacks.

The Harris campaign last week updated its online biography of Walz, which previously referred to him as a “retired command sergeant major” and now says he once served at that rank.

At a campaign rally last week that also served as Walz’s coronation as her running mate, Harris referred to him as “sergeant major.” Walz was also criticized for misstating his rank during the 2018 Minnesota gubernatorial election, and during his time in Congress he was frequently referred to as “sergeant major.”

Vance and Republicans also pointed to a clip first circulated by Harris’ campaign team itself in which he expressed his support for gun control. In it, Walz said he had carried military weapons “in war.”

“I never criticized what Tim Walz did when he was in the military. I criticized his decision to retire, and most importantly … I criticized his lies about his own past,” Vance said during the interview on CNN on Sunday. “This is a guy who was caught on video saying, ‘I carried a gun in war.’ He never went to war.”

The Harris team issued a statement to news outlets over the weekend saying Walz had “misspoken” at the time.

As Republican attacks against Walz increase, Democratic congressmen with military backgrounds are rushing to his aid.

“We saw 20 years ago with the shooting down of John Kerry, who served honorably in Vietnam, that we cannot expect baseless attacks to fail because of their own lies,” Democratic Rep. Jake Auchincloss of Massachusetts, a Marine Corps veteran, said at a Democratic National Committee news conference last week.

“Swift-boating” refers to the infamous and debunked 2004 campaign scam that denigrated Democratic presidential candidate John Kerry’s involvement in the Vietnam War. The man believed to be the architect of the Swift Boat attacks, Chris LaCivita, a Navy veteran, is now co-manager of the Trump campaign.

Auchincloss said Walz decided to run for Congress before his battalion was notified of the deployment to Iraq and that “we have officers and men who have all said he was an exemplary, admirable soldier.”

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