No. I don't think it would work all that well to do Fallout outside America. But if you are going to do it outside America don't do it in a country that:
A)Is culturally very simular to America in the 1950's.
B)Doesn't play a very important role in Fallout universe.
If your going to do a Fallout outside America do it in China. It plays an important Pre War role in the Fallout universe, meaning there's a certain amount of pre existing lore to build on and it's very, VERY different to America meaning you could have a radically different Fallout game while retaining elements that keep it grounded within that universe (Ghouls, mutated animals, robots, a dark sense of humour).
I've never seen post apocalyptic China, or many games set in China at all for that matter. If your going to do something different make it Different with a capital D, don't do something safe and boring.