Ruger was previously the vice president for research and policy at the Charles Koch Institute and the vice president of foreign policy at Stand Together. Before that, he was an associate professor (with tenure) in the Department of Political Science at Texas State University and an adjunct assistant professor at the LBJ School of Public Affairs at the University of Texas-Austin.

Ruger is a veteran of the Afghanistan War and was awarded the Defense Meritorious Service Medal, among other decorations. He remains an officer in the U.S. Navy (Reserve Component). Ruger was nominated to serve as the U.S. Ambassador to the Islamic Republic of Afghanistan and was a prominent advocate for ending America’s participation in the war there. Ruger was appointed by the president to the Fulbright Foreign Scholarship Board in 2020.

Ruger has written op-eds for numerous outlets such as The New York Times, The Washington Post, and Los Angeles Times, and he has been interviewed frequently for television and radio, appearing on Fox News, MSNBC, and CNN. He serves on several non-profit boards, including the Center for the National Interest, Defense Priorities, and the John Quincy Adams Society, as well as the Advisory Board of the Policing Project at the New York University School of Law. Ruger is a life member of the Council on Foreign Relations.

Ruger earned his PhD in Politics from Brandeis University and an AB from the College of William & Mary. His scholarship has appeared in a number of academic journals including International Studies Quarterly, Review of Political Economy, Economics of Governance, Civil Wars, and Armed Forces and Society. His most recent scholarship examines the relationship between military service, combat experience, and civic participation. Ruger is the author of the biography Milton Friedman and co-author of two books on state politics, including Freedom in the 50 States (now in its 6th edition).

Ruger resides in Great Barrington, MA. He is married to Jennifer Ruger and has two sons, Caleb and Mason.