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The former MMA fighter running DHS

Markwayne Mullin, a Trump loyalist with an unconventional record, takes over Homeland Security at a moment of crisis.

Senators Continue Work On Capitol Hill
Senators Continue Work On Capitol Hill
Sen. Markwayne Mullin (R-OK) arrives at the Capitol on March 23, 2026.
Heather Diehl/Getty Images
Caitlin Dewey is a senior writer and editor at Vox, where she helms the Today, Explained newsletter.

President Donald Trump got a mulligan in former Sen. Markwayne Mullin — a second shot at filling the top job at the Department of Homeland Security. Trump fired his first pick, Kristi Noem, amid mounting criticism of her leadership and management of the agency.

Mullin, a plumber-turned-MMA fighter-turned-firebrand politician, was confirmed to his new post on Monday. Now, he takes over an agency muddling through a series of ugly messes, from a funding shutdown that’s causing chaos at US airports to an aggressive, and often violent, mass deportation campaign.

Is Mullin the guy to clean all this up? Only time will tell. But there are some clues in his (genuinely entertaining, often surprising) record. Today, we take a look at the man newly charged with overseeing US border security, immigration enforcement and emergency response… at a moment when that’s a pretty difficult job.

Who is Markwayne Mullin?

As his concatenated first name might suggest, Markwayne Mullin contains multitudes. The 48-year-old Republican has worked as both a US senator and a plumber. He’s a hardcore MAGA conservative and an enrolled citizen of the Cherokee Nation. He’s a figurative and literal fighter who once publicly challenged a union leader to a fistfight…and then went on to become his close personal friend.

For our purposes, however, it’s probably most important to understand that Mullin was, until his confirmation on Monday, a first-term senator known both for his outspoken style and his close relationship with Trump. He has friends on both sides of the political aisle, but no experience in law enforcement.

How did Mullin get into politics?

Mullin was running his family’s plumbing business in Oklahoma when he first ran for Congress in 2012. Mullin was reportedly frustrated that the Affordable Care Act would force him to provide health insurance to his employees, and made opposition to the ACA a major part of his platform. He campaigned under the slogan “not a politician, a businessman” — and won with more than 57 percent of the vote.

Mullin served in the House for 10 years before running to fill retiring Sen. Jim Inhofe’s seat in 2022. In the Senate, he was the only sitting senator without a bachelor’s degree and the only Native American.

Mullin is fiercely loyal to Trump, who took a special interest in Mullin’s teenage son after the boy suffered a brain injury. The lawmaker has also been involved in a series of (sometimes outlandish) controversies.

What kinds of controversies has Mullin been involved in?

Mullin is one of the country’s wealthiest senators, with assets valued somewhere between $29 million and $97 million in 2024. (Disclosure rules allow lawmakers to report their assets within broad ranges — hence the gap in those numbers.) Mullin was a rich man when he entered politics, but his wealth has ballooned since then. His prolific stock-trading has drawn particular scrutiny from both journalists and watchdog groups, who suggest he may have profited from non-public knowledge and say he’s sometimes failed to disclose investments.

Mullin has made headlines for flashier reasons, too. In 2021, he repeatedly tried to embark on a rogue rescue mission to Afghanistan as US forces withdrew. Then there’s the time he infamously challenged Teamsters Union President Sean O’Brien to a fight during a 2023 Senate committee hearing. Sen. Bernie Sanders had to intervene.

Is Mullin expected to bring that chaotic energy to DHS?

No one has a crystal ball, of course. But Mullin struck a conciliatory tone during his Senate confirmation hearings. Among other things, Mullin said he would require ICE agents to obtain judicial warrants before entering private homes in most cases and work cooperatively with “sanctuary cities.”

Before his nomination to the DHS job, Mullin was also reportedly working with a friend in the House to broker a bipartisan compromise to end some of ICE’s more controversial new tactics, including enforcement actions at sensitive places like hospitals, schools, and churches. (Mullin is, despite his partisan voting record, known for having close Republican and Democratic friends — some of whom he met in the congressional gym, where he leads a bipartisan workout group.)

So…does that mean things go back to normal now?

Given Mullin’s commitment to Trump and his agenda, you probably shouldn’t expect to see a big about-face at DHS under his leadership. Mullin is fundamentally a Trump loyalist, said Reese Gorman, a political reporter at NOTUS, in conversation with my colleague Sean Rameswaram: “I think that you won’t necessarily see a lot of change in the rhetoric or the mission of deporting people.”

But that mission might look and feel a bit different under Mullin. Sen. Martin Heinrich, one of two Democrats to support Mullin’s confirmation, said that he trusted the Oklahoma lawmaker could not “be bullied” by the White House. During his hearing, Mullin also repeatedly promised to work with Democrats.

“My goal in six months is that we’re not in the lead story every single day,” he said. “My goal is for people to understand we’re out there, we’re protecting them, and we’re working with them.”

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