Donald Trump announced that Kristi Noem will step down as U.S. Secretary of Homeland Security at the end of March, following mounting criticism over her handling of immigration enforcement and a controversial $220 million advertising contract.
Posting on his Truth Social platform on Thursday, Trump said he plans to nominate Markwayne Mullin, a Republican senator from Oklahoma, to lead the U.S. Department of Homeland Security. The appointment will require confirmation by the United States Senate.
Noem, a former governor of South Dakota, became one of the most visible figures in the administration’s immigration crackdown. She frequently used social media to highlight cases involving immigrants accused of crimes and adopted strong rhetoric in support of the administration’s enforcement strategy.
Her tenure came under intense scrutiny this week during congressional hearings, where Democrats and several Republicans questioned her leadership and raised concerns about a $220 million advertising campaign that prominently featured Noem. The contract was reportedly awarded to two long-time Republican political operatives without a standard competitive bidding process.
The campaign included promotional material showcasing Noem in dramatic settings, including a scene of her riding a horse near Mount Rushmore in her home state.
Trump told reporters he had not personally approved the advertising campaign, although Noem told Senator John Kennedy during a congressional hearing that the president had signed off on it.
Noem also faced heavy criticism earlier this year after two U.S. citizens were fatally shot by federal immigration agents in Minneapolis. She initially labeled the incident an act of “domestic terrorism,” but later-released video evidence raised doubts about the claim that the victims were violent aggressors.
The backlash forced the administration to scale back sweeping immigration enforcement operations in the state and move toward a more targeted strategy. Democrats in the U.S. House of Representatives later introduced impeachment measures against Noem, while at least two Republican lawmakers publicly called for her removal.
Trump said Noem will instead serve as an envoy at an upcoming Western Hemisphere policy summit scheduled to take place in Miami.
During her leadership, immigration enforcement agents conducted large-scale operations in major cities including Los Angeles, Chicago and Washington, D.C., targeting suspected immigration offenders in neighborhoods, workplaces and public areas.
The change in leadership comes as the administration faces political pressure over its immigration strategy. While border crossings along the U.S.–Mexico border dropped sharply under Trump’s restrictive policies, critics argue enforcement actions have also led to the detention of non-criminal migrants and, in some cases, U.S. citizens.
Mullin, who served in the U.S. House of Representatives for a decade before becoming a senator in 2023, supports Trump’s hardline immigration agenda. Speaking to reporters after the announcement, he said he had not expected the nomination and described Noem as a friend.
“She was asked to do a very difficult job,” Mullin said, adding that there is an opportunity to build on the administration’s achievements while also addressing areas where policies “didn’t go quite as planned.”
The nomination now heads to the Senate, where Republicans hold 53 of the 100 seats. However, some lawmakers have expressed doubt that confirmation could happen before the end of March due to procedural requirements and ongoing political disputes over immigration funding.
