Elbridge Colby

Co-Founder and Principal

Elbridge Colby is co-founder and principal of The Marathon Initiative, a policy initiative focused on developing strategies to prepare the United States for an era of sustained great power competition. He is the author of the forthcoming The Strategy of Denial: American Defense in an Age of Great Power Conflict (Yale University Press, 2021).

Previously, Colby was from 2018-2019 the Director of the Defense Program at the Center for a New American Security, where he led the Center’s work on defense issues.

Before that, he served as the Deputy Assistant Secretary of Defense for Strategy and Force Development from 2017-2018. In that role, he served as the lead official in the development and rollout of the Department’s preeminent strategic planning guidance, the 2018 National Defense Strategy (NDS). The NDS shifted the Department of Defense’s focus to the challenges to U.S. military superiority and interests posed by China in particular followed by Russia, prioritizing restoring the Joint Force’s warfighting edge against these major power competitors. He also served as the primary Defense Department representative in the development of the 2017 National Security Strategy.

Prior to this, Colby was from 2014 to 2017 the Robert M. Gates Senior Fellow at the Center for a New American Security. From 2010 to 2013 he was principal analyst and division lead for global strategic affairs at CNA. Earlier in his career he served for over five years in the U.S. Government working on a range of strategic forces, arms control, WMD, and intelligence reform matters, including service with the Coalition Provisional Authority in Iraq in 2003 and with the Office of the Director of National Intelligence during its stand-up in 2005-2006. Colby has also served on the staff of a number of government commissions, including the 2014 National Defense Panel, the 2008-2009 Strategic Posture Commission, and the 2004-2005 President’s WMD Commission.

Colby’s work has appeared in outlets such as Foreign Affairs, The Wall Street Journal, The Washington Post, The New York Times, Foreign Policy, and The National Interest as well as in international outlets such as Asahi Shimbun, Yomiuri Shimbun, Nikkei Asia, Frankfurter Allgemeine Zeitung, Le Figaro, Survival, Internationale Politik, Die Zeit, The Taipei Times, Hankook Ilbo, Limes, The New Straits Times, and The Manila Standard. He is also the author of many book chapters, reports, and articles on defense and foreign policy issues. He has testified a number of times before Congress and the U.S.-China Economic and Security Review Commission. Colby is a recipient of the Distinguished and Exceptional Public Service Awards from the Department of Defense and of the Superior and Meritorious Honor Awards from the Department of State. A member of the Council on Foreign Relations and the International Institute of Strategic Studies, Colby is a graduate of Harvard College and Yale Law School.


Deter China’s military invasion of Taiwan

47 News | As the conflict between the United States and China deepens and tensions in the Taiwan Strait are worried, Elbridge Colby, who participated in the formulation of the strategy for China as Assistant Secretary of Defense under the former US administration of Trump,....

Pentagon to Speed Up Efforts to Counter China

The Wall Street Journal | At this point, the say-do gap is the problem,” said Elbridge Colby, a former Pentagon official who played a key role in developing the national defense strategy during the Trump administration....

The New Transatlantic Security Agenda

Fondation pour la Recherche Stratégique | FRS and U.S. Embassy & Consulates in France are pleased to invite you to a webinar entitled "The New Transatlantic Security Agenda", which will be held online on Wednesday, March 10, from 4:30 pm to 5:30 pm (CET)...

Sources of Chinese Conduct: A Debate

CFTNI | More than a half-century ago, George Kennan published an analysis of the sources of Soviet conduct that helped to shape US policy toward Moscow throughout the Cold War. More recently, the State Department’s Policy Planning Staff...

Defending Taiwan is growing costlier and deadlier

The Economist | Rousing music accompanies the h-6k, a hulking Chinese bomber, as it sweeps up into a pink sky. Moments later, its pilot presses a red button, with the panache and fortitude that only a People’s Liberation Army (pla) officer could muster, and a missile streaks towards the island of Guam...

A New Bargain

Internationale Politik | The rapid rise of China is inevitably forcing a major shift in the US-European relationship. It is time for both sides to root the transatlantic bond in shared interests, rather than often ill-defined values. Fortunately, such a basis exists.....

America’s New Defense Strategy

Center for a New American Security | On May 17, 2019, the Center for a New American Security (CNAS) and Foreign Policy (FP) welcomed visitors for an on-the-record discussion....

The Indo-Pacific After INF

The Heritage Foundation | After six years of failed attempts to get Russia to return to compliance with the Intermediate-Range Nuclear Forces (INF) Treaty obligations, the U.S. ...

Great Power Escalation

Georgetown University, Walsh School of Foreign Service | The Inaugural Theory and Practice of Security Conference: Nuclear Weapons and International Security Tuesday, March 19, 9:00 – 4:30, Lohrfink Auditorium, Georgetown University...

Take India’s Side, America

WSJ Opinion | The moment of maximum danger in the latest India-Pakistan conflict appears to have passed. But after a major attack by Pakistani militants on an Indian military base...

Do Nuclear Weapons Matter?

Foreign Affairs | Every year, world powers spend vast sums to upgrade and maintain nuclear arsenals and to prevent their spread to other nations—notably, to North Korea...

Additional Articles


Media Commentary


Book Chapters

  • “A World Order Critique of Nuclear Abolition,” in Global Nuclear Disarmament: Strategic, Political, and Regional Perspectives. N. Hynek and M. Smetana, Eds., Routledge, 2016.
  • “The Need for Limited Nuclear Options,” in Challenges in U.S. National Security Policy. D. Ochmanek and M. Sulmeyer, Eds., RAND Corporation, 2014.
  • “The United States and Discriminate Nuclear Options in the Cold War,” in On Limited Nuclear War in the 21st Century. J. Larsen and K. Kartchner, Eds. Stanford University Press, 2014.
  • “Defining Strategic Stability: Reconciling Stability and Deterrence,” in Strategic Stability: Contending Interpretations. E. Colby and M. Gerson., Eds. Strategic Studies Institute, 2013. (Also volume co-editor.)
  • “Why Nuclear Deterrence is Still Relevant” in Deterrence: Rising Powers, Rogue Regimes, and Terrorism in the Twenty-First Century. A. Lowther Ed., Palgrave MacMillan, 2012.
  • “U.S. Nuclear Weapons Policy and Policymaking: The Asian Experience,” in Nuclear Weapons and NATO. J. McCausland et al, Eds., Strategic Studies Institute, 2012.
  • “U.S.-Central European Relations After the ‘Pivot,’” in Navigating Uncertainty: U.S.-Central European Relations, Center for European Policy Analysis, 2012.
  • Chapters on the U.S. nuclear force, U.S. alliances, deterring WMD terrorism, and ways to address the challenge of a nuclear Iran in In the Eyes of the Experts: Analysis and Comments on America’s Strategic Posture. Bolz, Ed., U.S. Institute of Peace, 2009. (Compendium of memoranda drafted for the Congressional Commission on the Strategic Posture of the United States.)

Select video panel appearances and interviews