You may be interested to know that some time in the last decade the Russians clearly signalled they would be prepared to use nuclear weapons in Europe. Brilliant play since they know the US sentiment around preparedness to enter another conflict that isn’t theirs.
By simply signalling they forced the US to consider other options hence the decisions to deploy tactical nuclear capabilities not subject to the same rules as strategic nuclear weapons. And last I heard they were deploying these tactical capabilities to a sub class also responsible for SSG.
I’m very curious to understand whether Russian simply signalling in the way that they did has caused the US to strategically compromise their second strike guarantee. That would mean that by simply introducing the idea they have let the US take the mutually assured destruction elements off the table that made it so risky to begin with.