If nuclear warfare is totally illegitimate even for individuals defending themselves against criminal assault, how much more so is nuclear or even "conventional" warfare between States!
It is time now to bring the State into our discussion. The State is a group of people who have managed to acquire a virtual monopoly of the use of violence throughout a given territorial area. In particular, it has acquired a monopoly of aggressive violence, for States generally recognize the right of individuals to use violence (though not against States, of course) in self-defense. (Professor Robert L. Cunningham has defined the State as the institution with "a monopoly on initiating open physical coercion.")”