The best explanation I can offer from the misguided belief that the Enclave was explicitly restricted to the West Coast is that people assumed that much like the Mariposa Base with its FEV experimentation it was something exclusive to that general area. [spoiler:14dd45ba4a] That's a pretty terrible explanation, but people do that quite often, they get the details mixed up and it's understandable. As for FEV, I'm somewhat certain that was something the developers had always intended to be isolated, rather than being spread to the East Coast, however I'm guessing Bethesda's squirreling out of that hitch would be "Well, it's not the same FEV."[/spoiler:14dd45ba4a] The Enclave in Fallout 3 was one of the few things that did not disappoint me, but that's just because they were never that spectacular in Fallout 2, but the dialog was still subpar as I mentioned earlier in the thread. I think they could've done a bit better with the exposition at Raven Rock, as it was, it was too short. The whole [spoiler:14dd45ba4a]Eden versus the Enclave Soldiers[/spoiler:14dd45ba4a] bit was admittedly neat and one of my favorite part of the Main Quest. EDIT: Whoops, forgot to spoiler some juicy stuff.