H. R. McMaster is the Fouad and Michelle Ajami Senior Fellow at the Hoover Institution, Stanford University. He is also the Bernard and Susan Liautaud Fellow at the Freeman Spogli Institute and lecturer at Stanford University’s Graduate School of Business. Upon graduation from the United States Military Academy in 1984, McMaster served as a commissioned officer in the United States Army for thirty-four years.

He retired as a Lieutenant General in June 2018 after serving as the 25th Assistant to the President for National Security Affairs. He holds a PhD in military history from the University of North Carolina at Chapel Hill. He is the author of the bestselling books 'Battlegrounds: The Fight to Defend the Free World' and 'Dereliction of Duty: Lyndon Johnson, Robert McNamara, the Joint Chiefs of Staff and the Lies that Led to Vietnam'. In August 2024, McMaster released his most recent book, 'At War with Ourselves: My Tour of Duty in the Trump White House. McMaster is the host of 'Battlegrounds: Vital Perspectives on Today’s Challenges' and is a regular on 'GoodFellows', both produced by the Hoover Institution. He is a Distinguished University Fellow at Arizona State University.