Beat me to it. And there was a lot of atmospheric testing long after WWII. I don’t think at any point people said “We’ve messing with the weather! Look at what we’ve done to the climate!” No. There was awareness of fallout. So atmospheric testing gave way to underground testing. And then simulated testing. Just made more sense, because radiation is bad.
But I don’t see how any sort of limited exchange would hurt the earth. Sure — it might screw up supply chains, cause casualties, disrupt several societies. It would be bad. But I don’t see the climate being a primary casualty.
So if we have a nuclear winter can we go back to driving SUVs?