If you google "100 year history of Europe" you will see that older people like Putin are very aware of how drastically borders and governments have changed, even including countries that have nuclear weapons. To say that no one is going to invade Russia today is accurate, but from the Russian perspective the future of Russia is far from secure, they feel like they have to fight to preserve Russia.
> they feel like they have to fight to preserve Russia.
I get that's part of what the propaganda is saying, and therefore some part of the population will believe it strongly. I am just saying it is not believable.
Certainly, they have to fight to preserve rule by Putin, which is all that is under threat. Failing to invade might have made him look weak. Pulling out would make him look weak. The moment he starts to seem weak, he's out, and shortly dead.
USSR's borders were not changed by external powers. And England? Do you mean the end of Empire? I'm not sure on the dates but it mostly predates nuclear deterrence.
If you are not sure you can google "European border changes over the past 100 years" and also Google "Dates that countries became nuclear"
As far as the USSR collapse having nothing to do with external powers, that is an interesting take, I thought the Cold War was a big part of it, but maybe not?
