President Donald Trump fired Homeland Security Secretary Kristi Noem on Thursday, March 5, 2026, marking the first Cabinet secretary to leave his administration in his second term. Trump immediately announced that Oklahoma Sen. Markwayne Mullin, a staunch ally, would replace her, effective March 31, 2026.
In a Truth Social post, Trump described Mullin as “Highly Respected” and praised Noem for having “served us well.” He revealed that Noem would transition to a newly created position: “Envoy for The Shield of the Americas,” where she will lead a new security initiative focused on the Western Hemisphere.
An administration official told NBC News that Trump’s decision stemmed from “a culmination of her many unfortunate leadership failures,” including fallout from immigration enforcement operations in Minnesota, a controversial multimillion-dollar ad campaign, allegations of infidelity, staff mismanagement, and ongoing feuds with leaders of agencies such as Customs and Border Protection (CBP) and Immigration and Customs Enforcement (ICE).
The official stated that Noem’s “drama sadly overshadowed and distracted from the Administration’s extremely popular immigration agenda, which will continue full force.”
Noem, in a post on X, expressed gratitude for her new role and highlighted her 13-month tenure at DHS, listing what she called “historic accomplishments” at the department. Close aide Corey Lewandowski, who faced scrutiny over his influence and potential conflicts in approving grants and contracts, is also expected to depart DHS.
Sen. Markwayne Mullin told reporters he was “super excited” about the opportunity and described it as “not a complete surprise,” citing his close friendship with Trump. He acknowledged the need for Senate confirmation and said the process would begin immediately.
Mullin, a former MMA fighter and House member who won a special election to the Senate in 2022, received the call from the White House switchboard during a Senate Republican lunch, prompting him to abruptly leave. If confirmed, Oklahoma Gov. Kevin Stitt would appoint a Republican to fill Mullin’s Senate seat until the November midterms, with no special election required under state law due to the term’s expiration this year.
Noem’s tenure was defined by her leadership of Trump’s aggressive immigration and deportation policies, including mass enforcement operations, border restrictions, and a $200 million (plus production costs) ad campaign urging voluntary departures by those in the U.S. illegally. The campaign, largely in English and featuring Noem, drew criticism and bipartisan scrutiny.
Her position became increasingly precarious after fatal shootings of two U.S. citizens by federal agents during immigration operations in Minneapolis, strained relations with the U.S. Coast Guard, and contentious congressional testimony this week. Noem declined to apologize for labeling the deceased Americans “domestic terrorists,” though she noted investigations into the deaths are ongoing.
During Senate and House hearings Tuesday and Wednesday, lawmakers grilled Noem on the Minneapolis deployment of federal troops, which involved controversial tactics and drew widespread criticism, as well as the ad campaign. Noem claimed Trump approved the multimillion-dollar effort—a assertion the White House firmly denied.
Republican Sens. Thom Tillis and Lisa Murkowski had previously called for Noem to resign as early as January, with Tillis stating he could not identify any “point of pride” in her tenure.
Noem, formerly the governor of South Dakota, delivered a keynote address at a law enforcement conference in Nashville shortly after the announcement but did not mention her impending departure from DHS.
White House Press Secretary Karoline Leavitt described Mullin as “extraordinarily qualified” and said the administration would work swiftly with the Senate for confirmation.
