Ian Williams

Fellow, International Security Program and Deputy Director, Missile Defense Project
Ian Williams

Ian Williams is a fellow in the International Security Program at the Center for Strategic and International Studies (CSIS) and deputy director of the Missile Defense Project, specializing in missile defense and strategic forces, missile proliferation, and deterrence. He is also managing editor of the CSIS website Missile Threat, an online clearinghouse for information and analysis on missile proliferation and missile defense systems. Ian has authored major CSIS studies on U.S. homeland missile defense, nuclear proliferation, and the use of missiles in the Yemeni civil war. He has also written extensively on Iranian and North Korean missile programs, Chinese strategic forces and military strategy, and NATO’s missile defense architecture. Ian has made numerous appearances on global news programs, including ABC, NBC, CNN, NPR, and the BBC. His commentary has appeared in newspapers such as the New York Times, Washington Post, USA Today, Newsweek, and others.

During his graduate studies, Ian directed research at the Missile Defense Advocacy Alliance. He interned at the Center for the Study of Weapons of Mass Destruction at National Defense University and the Arms Control Association. He holds a B.A. from Southern Illinois University and an M.S. in defense and strategic studies from Missouri State University, where he studied arms control, WMD proliferation, missile defense, and nuclear strategy. In 2014, Ian completed his master’s thesis, “Future Directions for the Proliferation Security Initiative.” Before entering the international security field, Ian worked in international education, living for extensive periods in Russia, Korea, and the United Arab Emirates. He also served for six years as an engineer in the U.S. Army Reserve.

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The Truth of the Matter

Putin’s Missile War

CSIS’s Ian Williams joins the podcast to discuss Russia’s use of advanced, and not-so-advanced missiles in its war against Ukraine and how deterrence of the Russian Air Force by Ukrainian air defenses has shaped the course of the war.

Podcast Episode by H. Andrew Schwartz and Ian Williams — May 24, 2023

CSIS the truth of the matter

Putin’s Missile War

This CSIS report explores Russia’s evolving missile campaign against Ukraine from the opening days of the invasion to present day, the sources of Russian underperformance, and the specific missile systems Russia has deployed.

Report by Ian Williams — May 5, 2023

North America Is a Region, Too

New threats and the specter of non-nuclear strategic attack require a new approach to U.S. air and missile defense. This study discusses the need for homeland cruise missile defense, outlines principles informing defense design, and develops and costs an architecture.

Report by Tom Karako , Ian Williams , Wes Rumbaugh , Ken Harmon , and Matthew Strohmeyer — July 14, 2022

Boost-Phase Missile Defense: Interrogating the Assumptions

The CSIS Missile Defense Project is pleased to rollout our new report, Boost-Phase Missile Defense: Interrogating the Assumptions.

Event by Tom Karako , Ian Williams , Masao Dahlgren , Lt Gen Trey Obering (USAF, ret.) , and Dr. Dean Wilkening — June 24, 2022

Boost-Phase Missile Defense

This CSIS study provides a fresh assessment of issues related to boost-phase defense, including how missile threats are evolving and broader technological trends. It examines prior boost-phase studies for lessons learned and highlights new intercept capabilities.

Report by Ian Williams , Masao Dahlgren , Thomas G. Roberts , and Tom Karako — June 24, 2022

Tracking Missile Threats

To help navigate the wide world of missilery, the CSIS Missile Defense Project recently released a newly upgraded website to track and explain both missile threats and missile defenses alike.

Commentary by Ian Williams — August 12, 2021

Geopolitical Implications of Scientific Innovation Trends in Northeast Asia

This event and the accompanying report discuss the implications of scientific innovations and emerging technologies on geopolitics in Northeast Asia. The discussed emerging technologies have substantial commercial and military consequences, areas that will both prove strategically important.

Event by and Seth G. Jones , Chris Fall , Kaitlyn Johnson , Ian Williams , Andrew Philip Hunter , Park In-kook , Boo Suk-Jung , Lee Guenwook , Kim Yoon , Dr. Jason Matheny , Shin Changhwan — June 18, 2021

Online Event: International Security at the Nuclear Nexus (Day 2)

Nuclear weapons issues lie at the heart of a wide range of national and international security subject areas, such as conventional/nuclear integration as well as machine learning and artificial intelligence, cyber and space.

Event by Tom Karako , Ian Williams , Eric Brewer , Lindsey R. Sheppard , and Rebecca Hersman — October 22, 2020