Elbridge Colby

Elbridge Colby
Official portrait, 2025
Under Secretary of Defense for Policy
Assumed office
April 15, 2025
PresidentDonald Trump
Preceded byColin Kahl
Personal details
Born
Elbridge Andrew Colby

(1979-12-30) December 30, 1979
Political partyRepublican
RelativesWilliam Colby (grandfather)
EducationHarvard University (BA)
Yale University (JD)

Elbridge Andrew Colby (born December 30, 1979) is an American national security policy professional who is currently the under secretary of defense for policy. He previously served as deputy assistant secretary of defense for strategy and force development from 2017 to 2018 during the first Trump administration. He played a key role in the development of the 2018 U.S. National Defense Strategy, which, among other things, shifted the U.S. Defense Department's focus to China.

In June 2018, Colby was appointed as director of the Defense Program at the Center for a New American Security (CNAS). In 2019 he co-founded the Marathon Initiative, a grand strategy think tank, with Wess Mitchell. In December 2024, President-elect Trump nominated Colby to serve as the under secretary of defense for policy.

Identifying as a realist, Colby believes China is the principal threat faced by the United States. He believes the US should shift its military resources to Asia to prevent a Chinese takeover of Taiwan. Colby supports reducing military aid to Ukraine.