President Donald Trump announced on social media Thursday that he is appointing Oklahoma Republican Senator Markwayne Mullin as the nation’s next Secretary of Homeland Security.
In his post, Trump said Mullin would begin his role on March 31. Mullin will be acting secretary until the Senate votes whether to confirm his appointment.
Trump described Mullin as “highly respected” and commended him as affable among his colleagues. He wrote that Secretary Kristi Noem would be moving to a previously nonexistent role as “Special Envoy for The Shield of the Americas.” He indicated the security initiative associated with her position would be announced Saturday.
The announcement comes after speculation that Trump would fire Noem, who has served in the role since January 2025. Noem, a Republican from South Dakota, has faced bipartisan criticism. The Department of Homeland Security, which oversees the U.S. Immigration and Customs Enforcement, came under fire when ICE agents killed multiple citizens in Minnesota. More recently, Trump was reportedly upset that Noem told Congress that the president supported a $220 million ad campaign prominently featuring Noem.
Mullin has served as one of Oklahoma’s two senators since 2023, after he was elected to fill the rest of Jim Inhofe’s term upon his retirement. Before that, he served for a decade in the House of Representatives. He also owns a plumbing business and other companies in Stilwell and is a citizen of the Cherokee Nation.
Mullin’s offices did not immediately respond to a request for comment.
Mullin’s appointment will leave one of Oklahoma’s Senate seats vacant. Gov. Kevin Stitt is responsible for appointing an individual to fill the rest of Mullin’s term, which will end in January 2027.
Stitt’s office released a statement supporting Mullin’s appointment
"Markwayne Mullin has been a fighter for Oklahoma and will fight to keep our nation secure. There isn’t a better choice to lead the Department of Homeland Security," Stitt said in the statement. "Oklahoma has been an example to the nation for smart immigration enforcement, and Markwayne will bring that common sense to DHS. I will be looking to appoint a strong, small government conservative voice to support President Trump and protect Oklahomans’ way of life."
Oklahomans will elect a senator to Mullin’s seat in November. Candidate filing is open through April 2.
Mullin is the only tribal citizen currently in the Senate. Cherokee Nation Principal Chief Chuck Hoskin Jr. congratulated the senator, calling his appointment historic. He said having a Cherokee Nation citizen serve in the U.S. Cabinet is a mark of esteem for the tribal nation.
“It is deeply encouraging to have someone with a keen understanding of federal Indian policy, law and justice elevated to such a critical leadership role within a powerful federal agency,” Hoskin said in a statement.
This report was produced by the Oklahoma Public Media Exchange, a collaboration of public media organizations. Help support collaborative journalism by donating at the link at the top of this webpage.
