At present, the US nuclear arsenal and modernization program remain heavily weighted toward strategic forces over tactical nuclear weapons. Strategic nuclear weapons are designed to destroy an adversary’s war-making capabilities, namely its military, economic, political and population centers of gravity. Strategic nuclear weapons encompass intercontinental ballistic missiles (ICBMs), strategic bombers, and nuclear ballistic missile submarines (SSBNs), designed to hit targets deep in an adversary’s territory. In contrast, tactical nuclear weapons are designed to destroy an adversary’s war-fighting capabilities. However, the US emphasis on strategic nuclear weapons potentially leaves it inflexible against adversaries prepared to wage limited nuclear war.