President Donald Trump announced Thursday that he is appointing Oklahoma Senator Markwayne Mullin as the next Secretary of the Department of Homeland Security, marking a major leadership shift within the administration’s national security team.
Mullin will officially assume the role on March 31, 2026, replacing current Homeland Security Secretary Kristi Noem, who will transition into a newly created diplomatic role focused on regional security across the Western Hemisphere.
Trump praised Mullin as a strong ally and a respected figure in Washington, highlighting both his legislative experience and his background outside of politics.
“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 wrote in a public announcement.
Noem to Lead New “Shield of the Americas” Initiative
As Mullin prepares to step into the Homeland Security role, Kristi Noem will move into a new position as special envoy overseeing a regional security strategy known as “The Shield of the Americas.”
According to Trump, the initiative will focus on strengthening security cooperation across the Western Hemisphere and will be formally introduced during an upcoming announcement in Doral, Florida.
“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 said.
The program is expected to address migration, organized crime, and cross border security challenges across North, Central, and South America.
Mullin’s Path From Congress to Homeland Security
Mullin has served in the U.S. Senate for three years after previously representing Oklahoma in the House of Representatives for more than a decade. Before entering politics, he built a reputation as a successful small business owner and competed as an undefeated professional mixed martial arts fighter.
Trump emphasized Mullin’s political loyalty and ability to connect with voters.
“A MAGA Warrior, and former undefeated professional MMA fighter, Markwayne truly gets along well with people, and knows the Wisdom and Courage required to advance our America First Agenda,” Trump wrote.
Mullin is also currently the only Native American serving in the United States Senate. Trump noted that the Oklahoma lawmaker has been an advocate for tribal communities throughout his political career.
Border Security Expected to Be Top Priority
Trump said Mullin will focus heavily on strengthening border security and cracking down on crime and drug trafficking, issues that have remained central to the administration’s domestic security strategy.
“Markwayne 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,” Trump wrote.
Questions Around DHS Advertising Campaign
The leadership change comes amid questions surrounding a Department of Homeland Security campaign discussed during a Senate Judiciary Committee hearing earlier this week.
During testimony Tuesday, Noem indicated under oath that Trump had been aware of a DHS campaign and had approved it before the department finalized a multimillion dollar contract tied to the initiative, according to a source cited by National Review.
Trump pushed back on that claim Thursday, stating that he had not been aware of the campaign and did not approve the effort.
The issue has added a layer of political scrutiny as the administration prepares for the transition in DHS leadership later this month.