> So the minute a 'Small Nuke' is used, we should just respond with the biggest nuke. No point dilly dallying, if we are all going to die we might as well get it over with faster and in a way that is to our advantage.
Yeah, it's one of those crazy nuclear doctrines. Another is Launch on Warning, or the idea you can use nukes tactically without escalation.
Now, think about what's the point of publishing such strategic information? Isn't it a huge disadvantage when the enemy can anticipate how you will respond? In reality, you declassify information which you want that your enemy knows. These mentioned policies are meant as a deterrence, they're a bit of "playing madman" captured as a policy, because they're thought to provide an advantage when the enemy believes them.
I believe that the US has war game scenarios where one side uses a nuke, without the situation escalating into an all-out war, but these are extremely sensitive and thus highly secret. You don't want your enemy to believe there is some way where they can get away with using nukes, so in public you only mention the doomsday scenarios.
So, overall, I believe that the actual nuclear doctrine differs from the one published and should be less crazy. Note also that the head of states are not bound by the doctrine.
> The issue is that Russia or China may not see it that way. They might see the small nukes as a different thing that doesn't deserve the response of the larger nuke.
Part of it is again the deterrence aspect. Russia has a clear conventional disadvantage in comparison to US / NATO, so threatening with tactical nukes is a way to deter NATO from directly engaging Russia. It is in Russia's advantage to at least pretend that they think that tactical nukes can be used without major escalation. Just like US wants others to think there's no way to win a nuclear exchange, Russia wants you to think there's no way to win a conventional conflict (because it will soon escalate to nukes).
I'm not saying it means they're completely bullshi*ing, but there can be again a gap between what they think and what position they're trying to project.
> Also note: we stopped making larger nukes for political reasons. There seemed to be no end to the size of 'Large' nukes. The H-Bomb seemed to scale as large as we ever wanted.
Nukes become impractically large / heavy in that size, and as you mention, more numerous smaller nukes do more damage.
10 * 10 Mt is more destructive than 1 * 100 Mt, but 1000 * 100 Kt is much more destructive still.