This book studies force, the coercive application of power against resistance, building from Thomas Hobbes’ observation that all self-contained political orders have some ultimate authority that uses force to both dispense justice and to defend the polity against its enemies. This cross-disciplinary analysis finds that rulers concentrate force through cooperation, conveyance, and comprehension, applying common principles across history. Those ways aim to keep foes from concerting their actions, or by eliminating the trust that should bind them. In short, they make enemies afraid to cooperate, and now they are doing so in cyberspace as well.