The weaker version of madman scenario is a head of state believing they can use nukes in a limited scope to achieve its political goals.
Imagine this scenario: the war in Ukraine goes for some more time, Russia starts to have economic problems and is desperate to settle it (without having to compromise), force Ukraine to surrender and demand sanctions to be lifted. So he uses a couple of small tactical nukes along the frontline to cripple Ukrainian forces. Civilian deaths are in tens of thousands.
Ukraine can't respond, but apparently some threat has been declared from US to prevent this scenario - NATO / US launches conventional strikes on Russian military installations within Ukraine. Russia is not able to respond symmetrically, so it drops a tactical nuke on a military base within NATO territory (in Eastern Europe, far from major population center) as a kind of last warning to step back. There are multiple ways how this can go from then on, but there are scenarios ending in a major or all-out nuclear exchange. Without the need for misunderstanding and madmans.
Note that the smallest tactical nuke, the Davy Crockett, is One-Million times smaller than the largest nuke ever tested (The Tzar Bomba).
USA Policy is that all nukes are nukes. The idea being that we've never wargamed a scenario where small nukes were used that didn't turn into the treadmill of larger and larger nukes anyway. (Well, they used a 50 ton nuke. We should respond with a 500ton nuke, then they respond with a 10,000 ton nuke. Then we respond with a 100kTon nuke. Then they respond with a 1Mton nuke....)
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.
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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.
It's not that the world is composed of madmen. It's that the world is composed of people with different points of view.
As such, Russia stockpiles tactical (aka: small) nukes. USA stockpiles strategic (aka: large) nukes.
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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.
A collection of 10x 10 MTon nukes would deal more damage than a single 100MTon nuke anyway. But there's nothing stopping us from making 10x 100Mton nukes.
There's a difference between stated policy, actual policy, and what people will actually do when in a given scenario. For example, the PRC has a stated nuclear no first use policy, but I don't think anyone really believes that if the Indian army were advancing on Beijing that nukes would actually be off the table.
> The idea being that we've never wargamed a scenario where small nukes were used that didn't turn into the treadmill of larger and larger nukes anyway. (Well, they used a 50 ton nuke. We should respond with a 500ton nuke, then they respond with a 10,000 ton nuke. Then we respond with a 100kTon nuke. Then they respond with a 1Mton nuke....)
> 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.
The French nuclear doctrine is actually the exact opposite of this: they have a small nuke (the ASMP-A) that's explicitly designed as a nuclear warning shot to make everyone stop and think for a second before escalating into full scale nuclear war.
So the minute a 'Small Nuke' is used, we should just respond with the biggest nuke.
In any case the U.S. has stated that it won't do that unless it was a close strike against a very close ally (NATO partner or similar, or their deployed units). Most likely won't reciprocate to a nuclear strike against just Ukraine (provided it were of "limited" scope such as a warning or sequence of tactical shots).
> 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.
Russia that knows that China and India will not accept a nuclear first use in an offensive war. More than that, nuking Ukraine would also the drive everyone else still dealing with Russia far far away, probably even Iran. Also, if Russia uses nukes to get a favourable deal, presumably involving conquering some parts of Ukraine, why would they nuke the land they plan to loot?
Yes that’s a plausible scenario. Another potential trigger is that Ukraine manages a deep strike into Russia which causes significant damage and a conventional reply is considered non-sufficient.
Look how much carbon we emit when we fight conventionally. Maybe throwing around few nukes might actually save some people in the long run by delaying global warming.
I don't know .. weapons are typically not as good at killing as we imagine. Not as good as slow, mundane things. They could kick up a lot of dust into stratosphere though. Bizzarely it might be a worthy trade in some potential (imaginary) scenarios.
This is also why online commenters thinking that the Ukraine war will not go nuclear are misguided.