From PBS NewsHour.

President Donald Trump announced Thursday that he is replacing Homeland Security Secretary Kristi Noem with Sen. Markwayne Mullin.

"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 said in a social media post.

Noem will become special envoy for the Shield of Americas, a new security initiative in the Western Hemisphere.

Her exit comes after her testimony this week before House and Senate committees, where she was pressed by both parties on a number of issues, including the deadly use of force against U.S. citizens in Minnesota. A few lawmakers called for her resignation in the hearings.

Trump reportedly spoke to Republican lawmakers about his frustration with her performances in those hearings.

During her time leading the Department of Homeland Security, Noem faced criticism from Democrats and some Republicans over her conduct while overseeing Trump’s immigration crackdown. The agency, which is currently affected by a partial government shutdown, has been roiled by widespread backlash over its aggressive tactics.

The job of Homeland Security secretary, a Cabinet position, requires Senate confirmation.

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