…Maybe this would belong better in GD or IMHO. I’m not sure.
Anyway, the question is: Under current American political and military policy, what could make the U.S. launch an attack using nuclear weapons, short of getting involved in a major nuclear confrontation with Russia or China?
The only situations that I could think of would be:
a) Retaliation for the use of a WMD (Nuclear, Biological, or Chemical) in an attack on the U.S. or her allies. Say, if Iraq had tried to nerve gas Kuwait during the recent war. Or if terrorists nuked Washington, or something.
And this one doesn’t really count as “launching an attack,” but I’ll include it anyway…
b) Blowing up asteroids; “cauterizing” regions infected with some horrible plague that threatened to wipe out humanity, etc. And I’m not sure about the practicality of the latter.