President Donald Trump said on Thursday that Senator Markwayne Mullin, a Republican from Oklahoma, will become the United States Secretary of Homeland Security effective March 31, 2026. The announcement was posted on Truth Social and included details about a parallel reassignment for the current DHS chief, Kristi Noem.
In his post, the president said Noem will transition from her duties at the Department of Homeland Security to serve as Special Envoy for The Shield of the Americas - a security initiative in the Western Hemisphere that the administration plans to unveil on Saturday in Doral, Florida. The administration described the change as a handoff timed to occur at the end of March, when Mullin will formally assume leadership of DHS and Noem will move to her new envoy role.
Mullin brings a background that includes a decade of service in the U.S. House of Representatives followed by a successful special election to the Senate in 2023. The announcement notes he has represented Oklahoma in Congress for a combined total of 13 years. The post also referenced Mullin's past as a mixed martial arts fighter and identified him as the only Native American serving in the Senate, describing him as an advocate for tribal communities.
Trump praised Noem's work while at the Department of Homeland Security, specifically singling out her efforts on border security, and thanked her for her service before naming Mullin as her successor. The president also highlighted his electoral performance in Oklahoma, noting that he won all 77 counties in the state during the 2016, 2020, and 2024 elections.
In outlining the incoming secretary's agenda, the announcement listed three principal priorities for Mullin's tenure at DHS: strengthening border security, addressing migrant crime, and combating illegal drug trafficking. These priorities were identified as central to the department's focus under his leadership.
The transition timetable places Mullin in the DHS role starting March 31, 2026, with Noem set to lead the newly announced Western Hemisphere security initiative thereafter. The Shield of the Americas is scheduled for formal introduction in Doral on Saturday, according to the announcement.
Contextual note: The information in this report is drawn from the administration's public announcement and the post made by the president on Truth Social.