By Meridith McGraw, Josh Dawsey and Rebecca Ballhaus

Caught in the middle of President Trump and billionaire Elon Musk's spectacular fallout is a Republican operative with close ties to both men.

Katie Miller, 33, is a former Trump White House staffer married to White House deputy chief of staff Stephen Miller. Over the last year, she became a top adviser to Musk and worked at his side as he slashed and reshaped the federal government from his position as the leader of the Department of Government Efficiency.

When Musk left the White House last week, Miller followed to work for Musk. During her time at the White House, she was designated a "special government employee," which allowed her to work for Musk and Trump -- and in the private sector -- simultaneously.

Miller's proximity to the world's most powerful man, the U.S. president, and the world's richest man, billionaire Musk, put her in an enviable position in Trump's Washington. She coordinated with White House officials the warm send off between Trump and Musk in the Oval Office one week ago, according to people familiar with the matter.

Then on Thursday, her current and former bosses went to war. At some point during the nasty battle on social media, Musk unfollowed Miller's husband, Stephen Miller, on X. The couple had spent extensive time with Musk at Mar-a-Lago, Trump's private Florida club, and in Washington.

Katie Miller didn't respond to requests for comment, but privately asked others to speak on her behalf. White House officials said they were trying to cool the temperature between Musk and Trump on Friday. Miller, her friends said, was in a tricky situation between competing interests.

"Katie Miller was a critical reason DOGE was able to get off the ground and deliver massive cuts to waste, fraud and abuse for the American people," said Karoline Leavitt, the White House press secretary.

Those close to Miller describe the mother of three as hardworking, detail-oriented, combative and protective of her husband, whose fervent positions on immigration and other issues have made him a target of Democrats. In interactions with White House staff, she sometimes veered from charming to abrasive, current and former colleagues said, and seemed to have limitless energy.

People who know Miller said she has a tattoo on the inside of her lip that says "YOLO," which stands for "You Only Live Once."

She has sometimes shifted her loyalties, and she has blurred ethical lines, working for clients lobbying the government while also working on government issues. Musk's company is deeply dependent on government subsidies and contracts.

Miller, a native Floridian, had a meteoric rise in Washington. She was hired in 2015 by Montana Sen. Steve Daines. "WIN THE DAY," she wrote on a whiteboard in her office in capital letters, according to Jason Thielman, a former senior aide to the Republican lawmaker, who said Daines viewed her as "the gold standard."

"Everything was always at full speed, full throttle," he said. Of her critics, he said: "Not everyone loves that kind of intensity in someone."

Thielman said Miller often seemed to win battles with reporters because she kept talking. "Sometimes, she just exhausted people and they gave her what she wanted," he said.

Miller's first job in the Trump administration came during his first term when she worked at the Department of Homeland Security. At DHS, former colleagues said, she was willing to spend hours researching cases to fight on the administration's behalf, and was involved in defending the administration's child separation policy.

"It got to the point where she could tell you from memory the status of every individual construction project," said Jonathan Hoffman, a former Trump DHS official. "She knew the data better than the Army Corps of Engineers guys running the project."

Later, she joined Vice President Mike Pence's office and was "always defensive and protective of her principal," said Marc Short, who served as Pence's chief of staff. "Every Trump White House had its divisions, but she was always willing to go to bat to protect the VP's prerogatives."

She met Miller when she was working at DHS -- and Miller was working as the architect of Trump's restrictive immigration and border policies.

Trump attended their wedding at his former hotel in Washington, joking in a toast that Katie Miller wouldn't forgive him for skipping it even though Stephen Miller might. Wedding guests included top administration officials and an Elvis impersonator.

Miller was on maternity leave from the vice president's office on Jan. 6, 2021, when Trump accused Pence of not having the "courage" to overturn his 2020 election defeat as rioters stormed the Capitol.

At a moment when much of Washington turned against Trump and he had an irreparable split with Pence, Miller was stuck between the two. Her husband continued to work for Trump. She continued to work for Pence.

Miller was put on the postpresidential payroll by Pence, partially because Pence advisers said she needed healthcare. Pence's office later cut ties with her after Stephen Miller began working with Trump in his postpresidency, and Trump continued to attack Pence. Pence advisers described the situation as untenable.

After Trump left office in 2021, Miller joined P2 Public Affairs, a Republican consulting firm and advised a number of political and corporate clients, and her ties to Trump helped draw new clients to the firm. A spokesman for the firm declined to comment.

She later became the main point of contact between Musk and Trump's campaign during the 2024 election. She often accompanied Musk to events, and later began advising Robert F. Kennedy Jr., who endorsed Trump and was nominated to lead the Department of Health and Human Services. She became an advocate of the "Make America Healthy Again" agenda.

In January 2025, when Miller was working as an adviser to Kennedy during the transition, she publicly lashed out at Pence and accused him of only having "family values" when it is "politically expedient." She went on to call Pence a "footnote of American history." Pence was opposed to Kennedy's confirmation.

"It's hard to explain her subsequent tweetstorm when Mike Pence kept her on the transition specifically to ensure her family had healthcare and he helped her family when she was on maternity leave," said Short, Pence's aide.

Miller was one of the first employees Trump announced for DOGE in December 2024.

Her role at DOGE caused tensions with the West Wing, where senior aides felt she didn't do enough to help persuade Musk to work with agencies and the White House. Several senior administration officials said she often said she spoke on behalf of Musk, and gave directives about what should be done at agencies and what should be communicated about the government's actions.

Some White House officials grew frustrated with Miller for not communicating what DOGE was doing at times, while others said she was their only source of information about the secretive group. Miller told others she was trying to keep up and sometimes didn't know herself. They also blamed her occasionally for erroneous information Trump shared that got him in trouble, including that the U.S. government was sending $50 million in condoms to Gaza.

Miller continued to work for private clients at P2, which worried White House officials. There, she often counseled clients on how to navigate the current Republican Party. Some of her clients, such as Apple and the Consumer Brands Association, secured meetings at the White House, administration officials said.

After The Wall Street Journal reported on her dual work, she quit P2. The firm said they expected her to come back at a later date, but she hasn't returned.

By the end of Miller's time in the White House, she was keeping a lower profile. Miller, long willing to do battle, wasn't talking to reporters anymore, she told White House officials.

This spring, an email went out to staff advising that special government employees didn't have walk-in privileges in the West Wing unless they were working personally with the president, according to people familiar with the matter. The email was viewed as being aimed at Katie Miller, who since her days in the vice president's office had a habit of walking in and out of offices -- not unlike Musk, the people said. A White House official said the email wasn't aimed at Miller.

Soon, she told colleagues she was going to work for Musk. She has praised Musk and his companies in recent posts on X. The banner photo on top of her X profile is a rocket taking off for the sky.

Write to Meridith McGraw at Meridith.McGraw@WSJ.com, Josh Dawsey at Joshua.Dawsey@WSJ.com and Rebecca Ballhaus at rebecca.ballhaus@wsj.com

(END) Dow Jones Newswires

June 06, 2025 19:15 ET (23:15 GMT)

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