Barry R. Posen is the Ford International Professor of Political Science at Massachusetts Institute of Technology and Director Emeritus of its MIT Security Studies Program. A leading scholar in grand strategy and defense policy, his influential works include Restraint: A New Foundation for U.S. Grand Strategy and The Sources of Military Doctrine. Posen continues to shape debates on global power shifts, U.S. force posture, and military intervention through his teaching, research, and commentary.