The United States must be able to convince our adversaries that Americans have the will and capability to inflict punishment on them in response to an act of aggression such that they would not carry out the act of aggression in the first place, and so the United States won’t have to inflict the punishment it promises.

The U.S. Defense Department contains an inventory of roughly 7,100 nuclear warheads. About 4,760 are active, while approximately 2,340 warheads are retired, but still intact. The retired warheads are in storage and await dismantlement. Here is what you should know about nuclear weapons: