The theory that the threat of nuclear war is enough to prevent an attack is called

The theory that the threat of nuclear war is enough to prevent an attack is called: Nuclear deterrent

The theory is based on the likelihood that every nations would fear a mutual destruction when initiating attack to countries that own nuclear weapon. Even if a country emerge victorious from a nuclear war, the damage that caused by opposition's nuclear would damage the environment of the victors for decades.

C. Nuclear deterrent

im so sorry i dont know

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".