Short answers, pulled from the story.
The position was created by the Homeland Security Act, passed following the terrorist attacks of the 11th of September 2001. The first confirmed secretary took office on the 24th of January 2003.
Markwayne Mullin is the current Secretary of Homeland Security. He was sworn in on the 24th of March 2026, after being confirmed by the Senate 54-45.
The department includes the Coast Guard, U.S. Customs and Border Protection (which contains the Border Patrol), U.S. Immigration and Customs Enforcement, the United States Secret Service, the Transportation Security Administration, and the Federal Emergency Management Agency, among others.
Two acting secretaries had their tenures ruled unlawful: Kevin McAleenan, who served as Commissioner of Customs and Border Protection, and Chad Wolf, who served as Under Secretary for Strategy, Policy, and Plans.
The Homeland Security Act of 2002 creates exceptions to the Federal Vacancies Reform Act of 1998, placing the Under Secretary for Management third in the line of succession. The secretary can also directly establish a succession order outside the standard statute.
The Office of the General Counsel employs over 3,000 attorneys. It provides legal advice, ensures homeland security policies are implemented lawfully, and represents the department in venues including U.S. immigration courts.