In war, risk is a zero-sum game where combatants have to make trade-offs between risk to themselves, the mission, and noncombatants. To resolve this tension, it is useful to consider how soldiers in combat make decisions about ethics and the use of force.
President Putin made three foundational assumptions in launching his war against Ukraine that should have been correct but were not. First, Putin assumed the invasion of Ukraine would be a quick and easy fight. Second, he assumed the world would denounce the invasion but tacitly allow it. Third, Putin assumed the war would deter NATO expansion.
