Seth Cropsey (born November 3, 1958) is an American neoconservative political figure. He is the author of Mayday: The Decline of American Naval Supremacy.
He is the son of Joseph Cropsey, noted Straussian political philosopher and professor at the University of Chicago. Graduated from Harvard-St. George School, Chicago, IL and St. John's College and received his M.A. from Boston College. From 1977–1980, he worked as a reporter for Fortune magazine, covering U.S. private enterprise and public policy. In 1981, Cropsey worked as speechwriter and assistant to Secretary of Defense Caspar Weinberger.
Between 1982–1984, Cropsey was Director of Policy at the Voice of America. He also served as Deputy Undersecretary of the Navy during both the Ronald Reagan and George H.W. Bush Presidential administrations, and in 1991, was the principal Assistant Secretary of Defense for Special Operations/Low Intensity Conflict & Interdependent Capabilities.
Between 1994–1998, Cropsey served as both the Director of the Heritage Foundation's Asia Studies Center and as the First Departmental Chairman and Professor of the George C. Marshall European Center for Security Studies in Garmisch-Partenkirchen, Germany.