Well, space travel is a major theme in many american sci-fi movies, comics, and TV shows of the 50's, so if done well, they could pull it off. However, since it is set in Europe... maybe the 50's theme should apply to european culture at the time???
Something to ponder...
@Tyler: Fallout isn't meant to be realistic, but more of a 50's view of a post-apocalyptic future.