President Donald Trump has announced that U.S. Senator Markwayne Mullin of Oklahoma will take over as Secretary of Homeland Security on March 31, 2026.

This change comes as current Secretary Kristi Noem steps down after months of controversy surrounding her leadership of the Department of Homeland Security. Noem will move into a new role as Special Envoy for “The Shield of the Americas,” a Western Hemisphere security initiative the administration plans to unveil in Florida.

Noem’s time at DHS has been marked by intense scrutiny. Members of both parties questioned her handling of immigration enforcement, especially after federal agents fatally shot two U.S. citizens during operations in Minneapolis. She also faced criticism for spending hundreds of millions of dollars on a nationwide ad campaign urging undocumented immigrants to “self‑deport,” a campaign that featured her prominently.

Reports indicate that frustration had been building inside the administration for months. Senior officials and lawmakers raised concerns about Noem’s decisions, spending, and internal conflicts within DHS. Her recent testimony before the Senate Judiciary Committee, where she was pressed about the ad campaign and other decisions, appears to have been a turning point.

Senator Markwayne Mullin, who served ten years in the U.S. House and three years in the Senate, is a strong supporter of Trump’s immigration and border policies. He is also the only Native American currently serving in the Senate. The administration describes him as a committed advocate for border security and the “America First” agenda.

Mullin will now take charge of a department responsible for immigration enforcement, border security, domestic threat prevention, and oversight of agencies such as ICE, CBP, TSA, FEMA, and the Secret Service. His appointment marks the first major Cabinet change of Trump’s second term.

This leadership shift signals a reset in the administration’s approach to immigration and border operations, especially after months of public criticism, congressional pressure, and internal disagreements over DHS strategy.

---

Works Cited

Kristi Noem out as DHS Secretary; Trump announces Sen. Markwayne Mullin as replacement. https://www.cbsnews.com/news/kristi-noem-out-as-secretary-of-homeland-security-markwayne-mullin/

Trump Fires Kristi Noem, Announces Markwayne Mullin Will Replace Her. https://www.yahoo.com/news/articles/trump-fires-kristi-noem-announces-190319935.html

Trump says Kristi Noem is stepping down as homeland security secretary. https://www.nbcnews.com/politics/trump-administration/trump-says-kristi-noem-stepping-homeland-security-secretary-rcna248719

4Noem out, Trump picks Mullin as DHS secretary – POLITICO. https://www.politico.com/news/2026/03/05/markwayne-mullin-noem-dhs-00814761

5Trump names Oklahoma Sen. Markwayne Mullin as new DHS secretary. https://kval.com/news/nation-world/trump-names-oklahoma-sen-markwayne-mullin-as-next-dhs-secretary-effective-march-31-kristi-noem-homeland-security-trump-administration-immigration-minnesota-shield-of-americas