Lawmakers from the Senate Armed Services Committee heard testimony on Capitol Hill March 27, 2025, from four of President Donald J. Trump's nominees for leadership roles within the Defense Department. Included among those nominees were Michael P. Duffey, nominated as the undersecretary of defense for acquisition and sustainment; Emil G. Michael, nominated as the undersecretary of defense for research and engineering; and Keith M. Bass, nominated as the assistant secretary of defense for health affairs.