Every one automatically assumes that the US will vaporize anyone who uses nukes successfully on us. I think that is an extremely unwarranted assumption.
Assume there was major damage to the US, one of these cities obliterated: San Francisco, LA, Seattle, or Anchorage. Assume casualties are say 500,000 to a million dead. Also assume that we have definitive proof it was North Korea.
How will China, South Korea, Japan, and all the rest of Asia feel about a dozen or more nukes detonated in NK? You can bet those governments would be burning up the diplomatic channels telling the US not to retaliate with nukes, or any other form of WMD.
This is what we will hear from the Asians: “Hey, revenge is useless. You gotta be big about this. It’s too bad they killed or wounded several million Americans and trashed your economy, but DON’T be lobbing nukes into territory so close to us. If you do, there will be dire results.”
And Europe: “You can’t spread that much radioactivity into the environment. Too bad about San Fran, but if you weren’t such hegemons, these things wouldn’t happen to you. Don’t nuke North Korea, or there will be serious consequences.”
The Left through out the world: “You deserved it. Your policies against the 3rd world have driven the smaller governments of the world to the brink. There was no other way for NK to force you to pay attention to their legitimate grievances.”
Do you think there is any country in the world that would support the US retaliating with nukes? Do you think any of the left in the US would support nuking NK? Any liberal politician? The pressures to NOT respond with nukes would be ENORMOUS. I am not at all sure that any US president would respond with nukes, even Bush. Certainly not Clinton, JC, or their ilk.