FEATURES: Special Commentary. “The Military as Social Experiment: Challenging a Trope” by Jacqueline E. Whitt and Elizabeth A. Perazzo. Teaching Strategy. “Stuff Happens: Understanding Causation in Policy and Strategy” by Andrew A. Hill and Stephen J. Gerras. “Comparative Strategy in Professional Military Education” by Jean-Loup Samaan. Nontraditional War. “Russia’s Military and Security Privatization” by Christopher R. Spearin. “Russia’s Frozen Conflicts and the Donbas” by Erik J. Grossman. Traditional War. “Fighting Russia? Modeling the Baltic Scenarios” by Ben S. Wermeling. “The Conventionality of Russia’s Unconventional Warfare” by Patrick J. Savage.