Alexander Velez-Green is performing the duties of Under Secretary of Defense for Policy. He was previously appointed as Senior Advisor to the Under Secretary of Defense for Policy.

Previously, Velez-Green was a senior policy advisor at The Heritage Foundation. His research focused on defense, deterrence, and alliance management, including tradeoffs affecting U.S. forces in key theaters. He was also the lead author of Heritage’s special report on U.S. defense strategy titled “The Prioritization Imperative: A Strategy to Defend America’s Interests in a More Dangerous World.”

Prior to Heritage, Velez-Green served as National Security Advisor to U.S. Senator Josh Hawley (R-Mo.). In this capacity, he staffed Senator Hawley on the Senate Armed Services Committee, where he was responsible for hearing preparations, drafting legislation, and related negotiations, in addition to advising on defense strategy and policy issues. As part of these duties, Velez-Green routinely engaged with the National Security Council, Department of Defense, and State Department. He also led regular delegations to the Indo-Pacific region to monitor the Chinese military threat and U.S. responses to it. Additionally, Velez-Green was lead drafter of the COVID-19 Origin Act, which received unanimous support in Congress and was signed into law in March 2023.

Velez-Green has been an adjunct staff member at the RAND Corporation. He also worked in the defense practice at Systems Planning and Analysis, Inc., and at the Center for a New American Security. His work in the latter organizations focused on strengthening nuclear and conventional deterrence in Europe and the Indo-Pacific, including analysis focused on emerging technologies.

Velez-Green has published in The Washington Post, The National Interest, The American Conservative, National Review, Newsweek, Bulletin of the Atomic Scientists, War on the Rocks, Lawfare, Defense News, and Defense One, among others. He has also published with the Belfer Center for Science and International Affairs, Center for Strategic and International Studies, and Royal United Services Institute, and spoken regularly at conferences in the United States and Europe.

Velez-Green graduated cum laude from Harvard College. He is a novice mountaineer and has lived, studied, and traveled in more than forty countries, including a backpacking trip from Cairo to Cape Town.