Elbridge Colby

Elbridge Colby is the Principal and Co-Founder of The Marathon Initiative, a non-profit research organization focused on developing the diplomatic, military, and economic strategies the United States will need to navigate protracted competition with great power rivals. He served as the Deputy Assistant Secretary of Defense for Strategy & Force Development from 2017 to 2018. He focuses on strategic deterrence, nuclear weapons, conventional forces, and intelligence.

Elbridge Colby is the Principal and Co-Founder of The Marathon Initiative, a non-profit research organization focused on developing the diplomatic, military, and economic strategies the United States will need to navigate protracted competition with great power rivals. He is also a Senior Advisor to the strategic advisory firm American Global Strategies.

From 2018 to 2021, Colby was a Senior Advisor to the consulting firm WestExec Advisors. From 2017 to 2018, Colby was the Deputy Assistant Secretary of Defense for Strategy & Force Development and played a key role in the development of the 2018 National Defense Strategy. He was a Robert M. Gates Senior Fellow at the Center for a New American Security, where he consulted extensively with the Office of the Secretary of Defense, U.S. Navy, U.S. Air Force, U.S. Strategic Command, and the U.S. Department of State. He previously served as the Deputy Head for National Security Personnel on the Mitt Romney pre-transition effort. He also was a Principal Analyst and Division Lead for global strategic affairs and Director of the Defense Program at the Center for a New American Security. Before that, he served in the U.S. Government, including as Policy Advisor to the Secretary of Defense’s Representative for the New Strategic Arms Reduction Treaty (New START), as an Expert Advisor to the 2009 Congressional Strategic Posture Commission, as a staff member on the President’s Commission on the Intelligence Capabilities of the U.S. Regarding WMD, with the Coalition Provisional Authority in Iraq, and with the State Department. Colby has also served as a consultant to a variety of U.S. Government entities on a range of defense and intelligence matters.

Colby is a term member of the Council on Foreign Relations, a member of the International Institute of Strategic Studies, and Co-chairman of the Washington, D.C. Advisory Committee of the Hamilton Society. He is a recipient of the Exceptional Public Service Award from the Office of the Secretary of Defense and of the Superior and Meritorious Honor Awards from the Department of State.

He focuses on strategic deterrence, nuclear weapons, conventional forces, and intelligence.

Colby authored The Strategy of Denial: American Defense in an Age of Great Power Conflict, co-edited Strategic Stability: Contending Interpretations, co-chaired a CSIS working group study on U.S.-China nuclear weapons issues entitled ‘Nuclear Weapons and U.S.-China Relations: A Way Forward’, and has published book chapters in a number of edited collections. He also publishes regularly on defense and foreign policy issues in publications such as The New York Times, The Wall Street Journal, Politico, The National Interest, Foreign Policy, War on the Rocks, and Orbis.

Colby received a BA in history from Harvard University in 2002 and a JD from Yale Law School in 2009.