As deputy staff director and general counsel to the House Armed Services Committee, Roger Zakheim has been on the front lines of hot-button national security and defense issues over the past year, advising the Republican-led committee on everything from the drawdown of troops in Afghanistan to defense budget cuts.

Zakheim turned 35 in August, but his influence already stretches beyond Capitol Hill. Last October, he was tapped to be part of GOP presumptive presidential nominee Mitt Romney’s national security and foreign policy advisory team, serving as co-chair of the defense working group. It was a testament to his expertise: The other co-chair is John Lehman, a former Secretary of the Navy in the 1980s and member of the 9/11 Commission.