Aidan Daly 
Markwayne Mullin on Tuesday was sworn in as new Department of Homeland Security secretary.
The Senate on Monday confirmed Mullin in a 54-45 vote. Mullin succeeds Kristi Noem, former DHS secretary and a Wash100 Award winner, and becomes the latest official to join President Donald Trump’s cabinet.
He takes charge of DHS at a time when the agency is managing a broad mission set that includes border security, cybersecurity, emergency response and infrastructure protection.
Discover the latest DHS IT business opportunities at the Potomac Officers Club’s 2026 Digital Transformation Summit on April 22. Sign up today!
Who Is Markwayne Mullin?
Markwayne Mullin is a Republican lawmaker and businessman who most recently served as a U.S. senator from Oklahoma before his confirmation as DHS secretary.
Born in Tulsa, Oklahoma, Mullin rose from the private sector, taking over his family’s plumbing business and building it into a multimillion-dollar enterprise before entering politics.
He first won election to the House in 2012 and became known as a staunch conservative and close ally of President Donald Trump, frequently aligning with the administration’s policy priorities. He won his Senate seat in 2022 and quickly became a visible figure within the Republican conference.
Mullin’s nomination to lead DHS capped a rapid political ascent from small-business owner to Cabinet official overseeing one of the federal government’s largest and most complex agencies.
What Did Mullin Say During his Confirmation Hearing?
During his Senate confirmation hearing, Mullin outlined a management-focused approach to leading DHS, emphasizing efficiency, accountability and coordination across the agency.
Mullin told lawmakers his top priorities for leading the agency.
“My goal in six months is that we’re not in the lead story every single day. My goal is for people to understand we’re out there, we’re protecting them, and we’re working with them,” he said.
Overall, Mullin presented himself as focused on strengthening DHS operations, improving oversight and maintaining continuity across the department’s core mission areas.
