We have no way of knowing, in retrospect, what the real risk of global nuclear war was. We live in the universe where the die roll came up "no", and we don't know if the odds of our survival were 99% or much less than that.

How do you weigh the certain death of millions vs. peace with a small chance of utter annihilation? I don't know, but I don't think it's as easy as you say.