This.
Fallout is based on the pre-war culture of the 50's in the US. Besides we already fought China in Operation Anchorage :sadvaultboy: and it was my least favorite DLC
I saw an interesting idea or even a large game mod in development awhile back on a post at nma.
It's set it an european country Britian I think using their -own- 50s culture of the time.
So yes it's viable. If chances weren't taken on interesting places, timelines, and story we wouldn't have Fallout, wasteland, nor other innovative franchises like Deus Ex.
For the time being most likely no, it'll be set in post-post-apocalyptic America(Including the annexed lands of Canada)