H.R. McMaster is a retired United States Army officer and a former National Security Advisor. He served in the Army for over 30 years, participating in various conflicts, including the Gulf War and the Iraq War. McMaster is known for his expertise in military strategy and history, and he has authored several books on these subjects. In 2017, McMaster was appointed by President Donald Trump as National Security Advisor, where he played a key role in shaping U.S. foreign policy. He left this position in 2018 and has since been involved in academia and public speaking, sharing his insights on national security and military affairs.