![The reentry of an unarmed Minuteman III ICBM after a test over the Marshall Islands on September 6, 2023. (US Army photo by Amy Hansen)](/sites/default/files/styles/16_9_sm/public/2024-06/8059034.jpg?h=8cdf5baa&itok=YvJnMVLv)
Robert C. O'Brien is the co-founder and chairman of American Global Strategies LLC. He was the twenty-seventh United States national security advisor from 2019–2021. O’Brien served as the president’s principal advisor all aspects of American foreign policy and national security affairs.