Soon after the defeat of Germany in 1945, the United States and the Soviet Union found themselves in a global struggle for power and influence. In contrast to previous great power competitions, which had often led to conventional armed conflict, nuclear weapons dramatically changed the risk calculus for both sides. Since combat operations between nuclear armed adversaries could lead to their mutual annihilation, geopolitical competition between them would now reserve military force for “coercion, intimidation, and deterrence.”