President Donald Trump announced Thursday that he is replacing Kristi Noem as Secretary of the United States Department of Homeland Security, naming Oklahoma Sen. Markwayne Mullin as her successor effective March 31, 2026. The change marks the first cabinet-level departure of Trump’s second term and follows days of scrutiny over Noem’s testimony before Congress and internal frustrations over the department’s management.
🚨 IT’S OFFICIAL: KRISTI NOEM IS OUT AT DHS, BEING REPLACED BY SEN. MARKWAYNE MULLIN
This comes after President Trump was reportedly angered by Noem’s testimony that Trump approved her $200M DHS ad campaign
PLEASE, @SenMullin: do NOT relent on mass deportations!
Mullin will… pic.twitter.com/a7t2CIILVJ
— Nick Sortor (@nicksortor) March 5, 2026
In a post on Truth Social announcing the decision, Trump wrote: “I am pleased to announce that the Highly Respected United States Senator from the Great State of Oklahoma, Markwayne Mullin, will become the United States Secretary of Homeland Security (DHS), effective March 31, 2026.”
Trump also praised Noem’s work at DHS while outlining her new assignment. “The current Secretary, Kristi Noem, who has served us well, and has had numerous and spectacular results (especially on the Border!), will be moving to be Special Envoy for The Shield of the Americas,” Trump wrote, describing the role as part of a broader Western Hemisphere security initiative that the administration plans to unveil in Florida.
The newly announced position—Special Envoy for the Shield of the Americas—will focus on security cooperation across the Western Hemisphere. Trump said additional details about the initiative would be released during an upcoming announcement tied to regional security coordination with Latin American partners.
Noem, a former governor of South Dakota and longtime political ally of Trump, had overseen the department during a period defined by the administration’s hardline immigration policies and expanded enforcement operations. Her tenure drew sustained scrutiny from lawmakers and advocacy groups, including criticism of enforcement actions, detention policies, and internal agency management.
Tensions surrounding her leadership intensified this week during testimony before the U.S. Senate Judiciary Committee. During the hearing, Noem confirmed that Trump had approved a roughly $220 million taxpayer-funded advertising campaign encouraging undocumented immigrants to self-deport, a campaign that prominently featured the DHS secretary herself.
Republican Sen. John Kennedy pressed Noem on whether the president had personally authorized the advertisements. According to reporting on the hearing, Noem affirmed that he had. The testimony reportedly angered Trump, who later denied having been aware of the campaign’s details.
The controversy added to broader concerns about management inside DHS, where reports of internal friction and leadership disputes had circulated for months. Some lawmakers from both parties had criticized the department’s operations and oversight of immigration enforcement programs.
Trump’s nominee, Mullin, has served in the Senate since 2023 after previously representing Oklahoma in the U.S. House of Representatives for a decade. A businessman and former professional mixed-martial-arts fighter, he has been a consistent supporter of Trump’s immigration and border-security agenda in Congress.
Searching “deportations” on his profile had good results. I think he’ll be great. pic.twitter.com/2elkc5mEGg
— Socrates the Chud (@SocratesTheChad) March 5, 2026
I am wondering what this new position at this new agency for Kristi Noem will be. Mullins is a no-nonsense kind of guy. I think he will be more aligned with Homan when it comes to attitude.
— Love Golden Retrievers (@Goldenmom1007) March 5, 2026
In his announcement, Trump described Mullin as “a MAGA Warrior, and former undefeated professional MMA fighter,” adding that the senator “knows the Wisdom and Courage required to Advance our America First Agenda.”
Trump also highlighted Mullin’s role in the Senate, writing that he “will work tirelessly to Keep our Border Secure, Stop Migrant Crime, Murderers, and other Criminals from illegally entering our Country, End the Scourge of Illegal Drugs and, MAKE AMERICA SAFE AGAIN.”
Mullin is expected to face Senate confirmation before formally taking office. Until then, the transition period runs through the end of March, when Noem is scheduled to step down from the department and begin her new diplomatic assignment tied to the Shield of the Americas initiative.
Featured image via X screengrab
