The Almanac of American Politics 2020 called Mac “one of Congress’ brainiest and most thoughtful members on national and domestic security issues,” and said that he “has long been at the forefront of national security issues.”  USA Today said Mac has “experience in Washington, a rare long view and a reputation for serious, thoughtful problem-solving.”

Serving on the House Armed Services Committee throughout his time in Congress, Mac was its Chairman from January 2015 to January 2019, the first Texan of either party to hold this position. When House Democrats won the majority in 2018, he became the Ranking Member of the Committee. Mac also served on the House Intelligence Committee for 14 years.

Mac has a proven ability to oversee large organizations with complex missions and dive deeply into specific issues within the context of the broader picture and longer-term trends. Whether engaging with foreign officials or working with those across the political spectrum, he has demonstrated an ability to bring others together for a common purpose.