Mara Karlin, PhD, is Director of Strategic Studies at the Johns Hopkins School of Advanced International Studies (SAIS). She is also an Associate Professor at SAIS and a nonresident senior fellow at The Brookings Institution. Karlin served in national security roles for five U.S. secretaries of defense, advising on policies spanning strategic planning, defense budgeting, future wars and the evolving security environment, and regional affairs involving the Middle East, Europe, and Asia. Most recently, she served as the deputy assistant secretary of defense for strategy and force development. Karlin has been awarded Department of Defense Medals for Meritorious and Outstanding Public Service, among others. She is the author of Building Militaries in Fragile States: Challenges for the United States (University of Pennsylvania Press; 2018).