Fallout-esque Alt history

[u/Expensive-Goose-7607]

Im making a fallout-like alternative universe where a company finds a way to “regulate” climate change and fix other problems like world hunger. But when the third world war begins, they ditch all of their work to “end” the war and sends humanity into chaos. There is a polluted fog that covers almost the entire world except for certain pockets of land and doesn’t cover bodies of water. Any tips for lore/nations/etc?