Hey all,
I'm pretty much swamped by my own projects but I found this document online, and it contains some interesting ideas for scenarious in SF2 that simulate the situation after a full nuclear exchange:
http://www.johnstonsarchive.net/nuclear/nuclearwar1.html
I'm not what you'd call in-the-know about thermonuclear devices but most of the projections here seem legit... Anyways, here are some interesting excerpts that could form a basis for campaigns:
Israel based campaign
Far east
Other notable ideas are latin american countries raiding the continental USA for resources and food wars all over the third world.
Overall, it's a pretty bleak read and certainly makes one happy that there never was a full scale nuclear exchange.. That said, the cold-war gone hot in Europe that SF2 and many other games simulate that is strictly conventional is rather naive I think, and this would be an interesting scenario, no?