MAD was manipulated by KGB propaganda. The Russians know that with proper civil defense, nuclear war can be won. The nuclear winter BS is the sister of the Global Warming hoax, preventing us from building shelters thinking the Soviets would not need it either.
Wrong.
How is nuclear war won?
What do you have when it is over, destroyed infrastructure, destroyed cities, destroyed agriculture and economy, destroyed transportation systems, destroyed everything?
It hardly matters whether 10% or 50% of the Russian population of 142 million survives if they come out of the rubble with winter (or spring, or summer) coming on, and nothing to eat, or to heat themselves with, or to shelter in, or to do, except to remember that they are now starving and defenseless and have weeks left of life.
How is that winning? Instead it is the end of Russia.