(WASHINGTON) -- In a notable moment from Sen. JD Vance's speech at the Republican National Convention last week, former President Donald Trump's newly picked running mate took aim at President Joe Biden's support of the Iraq War.
"When I was in the fourth grade, a career politician by the name of Joe Biden supported NAFTA, a bad trade deal that sent countless good jobs to Mexico," Vance told the Milwaukee crowd, adding, "When I was a senior in high school, that same Joe Biden supported the disastrous invasion of Iraq."
But in 2010, Vance himself expressed support for the war.
"I supported the Iraq invasion on the merits," Vance wrote in a 2010 article for "FrumForum," a conservative website run by David Frum, now the senior editor for The Atlantic, according to a post reviewed by ABC News.
Vance, who served as a combat correspondent with the U.S. Marines in Iraq in late 2005, is the first veteran on a presidential ticket since 2008.
In the FrumForum article, dated April 12, 2010, Vance discussed the complexity of the war in the wake of Wikileaks releasing a video of an Apache helicopter gunning down a group of Iraqi civilians.
"We can legislate laws of war and refine rules of engagement, but war will always be a grisly business," said Vance, writing under his previous name, J.D. Hamel, which he also used during his military service. "I'm not a peacenik, and I supported the Iraq invasion on the merits, but it's folly to send troops to do the toughest job and then be shocked by the attitude that some show while doing it."
Vance previously went by Hamel, his mother's husband's name, before later taking the name Vance, the name of his maternal grandmother.
In the piece, Vance also criticized then-President George W. Bush for failing to "emotionally prepare the American people for war."
"Of all of President Bush's mistakes, his failure to emotionally prepare the American people for war is perhaps the most severe. We ought to demand the best of our troops, and do whatever necessary to rectify mistakes, but the American people are too often confused or shocked when things like this happen," Vance wrote. "Maybe we wouldn't be if we understood the monumental difficulty of our task."
Vance's time writing for "FrumForum" -- whose editor, David Frum, is a vocal Trump critic -- has garnered scrutiny since the Ohio senator accepted the nomination as the Republican vice presidential nominee.
Vance's stance on the Iraq War appeared to turn more critical in the years following his 2010 article. In a 2016 op-ed in The New York Times, he lamented that Republicans, in 2008 and 2012, "ran candidates who refused to rethink the Bush foreign policy that led to Iraq."
"With the Islamic State on the rampage, Americans today look to a Middle East that is humiliatingly worse off than the way we found it," Vance wrote.
Speaking at the Heritage Foundations 50th Anniversary Leadership Summit in April 2023, Vance said that when he was a high school student, just prior to enrolling in United States Marine Corps in April 2003, he believed "what we would do in Iraq was transform it from a horrible dictatorship into a flowering democracy."
"I also hate to say not just that it didn't happen, not just that some of us were wrong, myself very much at the top of the list, even though I was only a high school student," Vance said last year, "but the people who were most wrong suffered no consequences."
Last year, Vance called the Iraq war an "unforced disaster" in a social media post.
"Twenty years ago we invaded Iraq. The war killed many innocent Iraqis and Americans. It destroyed the oldest Christian populations in the world. It cost over $1 trillion, and turned Iraq into a satellite of Iran. It was an unforced disaster, and I pray that we learn its lessons," Vance wrote.
In a statement to ABC News, Vance spokesperson William Martin said, "Like thousands of young men at the time, Sen. Vance enlisted in the U.S. Marine Corps near the start of the Iraq War. He ultimately came to the same conclusion as millions of other Americans: that the war he served in was a massive mistake."
"Too few leaders in Washington learned that lesson, but President Trump knew it from the very start," the statement continued. "Together, they will implement an America First agenda that actually serves our national security interests and avoids the foreign policy disasters that Joe Biden and Kamala Harris have overseen for the past four years."
Throughout his 2016 presidential campaign, Trump repeatedly claimed he did not support the 2003 invasion of Iraq or the U.S. intervention in Libya in 2011, despite previous public statements to the contrary. In an Howard Stern interview that briefly touched on the subject, Stern asked Trump, "Are you for invading Iraq?" to which Trump replied, "Yeah, I guess so. I wish the first time it was done correctly," referring to the 1990 Gulf War.
Trump, however, told NBC News in 2016, "I heard Hillary Clinton say I was not against the war in Iraq. I was totally against the war in Iraq."
"You can look at Esquire magazine from 2004 ... I was against the war in Iraq. I said it's going to totally destabilize the Middle East, which it has. It's been a disastrous war," Trump said, pointing to a comment he made over a year after the war began.