Host Carol Castiel talks with Barry Posen, Political Science Professor at MIT and Henry A. Kissinger Chair in Foreign Policy and International Relations at the Library of Congress, about the implications of the resignation of National Security Advisor General Michael Flynn and Posen’s research on US foreign policy and grand strategy, including relations with Moscow. Posen argues that the value of US alliances should be judged on their contribution to US security and like President Donald Trump, he believes US allies, like the European Union, need to contribute more to their collective defense.