U.S. President Donald Trump has tapped Stephen Miller to serve as White House chief of staff, a role that will see Miller replace Susie Wiles. The announcement was made via a post on Truth Social on Friday, following the Republican Party’s significant midterm election defeat earlier this week.

Background on Stephen Miller

Stephen Miller, 41, has long been a key figure in Trump’s administration. He is known for his role in shaping some of the president’s most controversial policies, particularly those related to immigration. Miller has been described as an architect of the administration’s mass deportation campaign.

Trump praised Miller in his Truth Social post, calling him “one of my most trusted advisors.” He said Miller would assume the new role from Susie Wiles on Monday.

Miller’s Political Career and Policies

Miller built a reputation as a conservative activist before joining Trump’s inner circle. He worked as a legislative aide to Republican members of Congress and Senator Jeff Sessions. He joined Trump’s 2016 presidential campaign in January and was credited with shaping the president’s messaging and political style.

During Trump’s first term, Miller was instrumental in pushing policies that led to the 2018 Department of Justice “Zero Tolerance” policy at the U.S. border. The policy led to widespread family separations. The policy was later modified via an executive order.

Miller also played a role in the administration’s attempts to end the Deferred Action for Childhood Arrivals (DACA) program, which allowed undocumented immigrants brought to the U.S. as children to live and work legally. The program stopped accepting new applicants in 2021.

He supported the 2017 travel ban on several Muslim-majority countries, a policy that faced legal challenges and was eventually upheld by the U.S. Supreme Court in a revised form.

Recent Activities and Controversies

Miller remained a close advisor to Trump during the 2024 presidential campaign and took on the role of deputy chief of staff for policy and homeland security adviser when Trump retook office in January 2025. He has helped orchestrate the administration’s mass deportation drive, which has led to increased immigration enforcement actions across the country.

In May 2025, Miller told Fox News that the administration had set a goal of a minimum of 3,000 arrests for ICE every day, with the number expected to rise. He also defended increasingly aggressive tactics by immigration agents, including the January killings of Renee Good and Alex Pretti in Minneapolis, which he initially described as acts against “terrorists.”

Miller has also been involved in efforts to expel individuals from the U.S. based on their support for Palestinian rights. Mahmoud Khalil, a former graduate student at Columbia University, filed a lawsuit against several Trump administration officials, including Miller, accusing them of orchestrating a conspiracy to single out non-citizen Palestinians. Khalil is currently facing deportation proceedings under Trump’s administration.

Miller has criticized pro-Palestinian voices in Congress, including U.S. Representative Rashida Tlaib, whom he has called “deeply anti-Semitic and deeply anti-American.” He has also defended Trump’s military actions in the Western Hemisphere, including the U.S. abduction of Venezuelan leader Nicolas Maduro and the idea that the U.S. could seize Greenland based on its military might.

“We live in a world in which you can talk all you want about international niceties and everything else, but we live in a world, in the real world … that is governed by strength, that is governed by force, that is governed by power,” Miller said in an interview with CNN in January.

Role of Chief of Staff

It remains unclear how Miller’s new position will affect his influence over Trump. The chief of staff is responsible for overseeing White House staff and hiring, maintaining the president’s schedule, and advising on policy. The role is often described as the “gatekeeper” to the presidency, controlling information flows and access to the president.

Democrats will take control of the U.S. House of Representatives and Senate in January and are expected to launch investigations into Miller’s role in the White House.