you don't know the Enclave then, if you know the Enclave's ideology, philosophy and whatnot then you'd know that they will never allow any filthy, mutant, wastlander or outsider in their organization, as they see anyone outside the Enclave fit only for slavery or eradication to make room for the true citizens of America, themselves (alteast in their minds), so it wouldn't make sense to make them joinable
I fits story wise your concerned about, Bethesda could come up with something. Your character's story in Fallout 3 was he is supposedly born in a Vault. Its not true, but the Enclave does not know that.
Bethesda has some really talented people so they would've made a storyline that would make sense for players to join the Enclave if they wanted to. Not that it matters anymore as the Enclave is dead. Triple dead (Oil Rig, Raven Rock, and then Nellis).
I do know the Enclave. I never played Fallout 2 but I did play 3 and what I did not know I researched and read about on the wiki. Pretty much joining the Enclave is almost no different from Bethesda giving players the choice to join Caesar's Legion or blowing up Megaton. Its all about player choice and there have been far worse games that have you do pretty bad stuff in a real world setting (GTA comes to mind). In Fallout games you have the option to cannibalize corpses and murder people in cold blood (practically you can shoot anyone in the game). Enclave isn't that far off. It might be a whole other degree of killing, but in the end its just a game. I'm not going to loss sleep bec. of exterminating megabits of computer programs in a virtual world environment on a computer screen.
because the Enclave treats anyone outside their organization as unfit for anything else than slavery or eradication and Vault Dwellers as lab rats, in Fallout 2 the Enclave just kidnaps Vault Dwellers and make them test subjects for horrible experiments, so even if the Lone Wanderer is a Vault dweller, he's still not born in the enclave and will still be treated as a lab rat or a pawn at best (Eden, treated you (Lone W.) as just a pawn and will likely exterminated once you exhaust your usefulness to him if he can)
and one more thing, joining the Legion is entirely difference, the Legion is not an elitist group, the legion likes to assimilate other groups into their own unlike the Enlcave, the Legion's recruiting style is the opposite of the Enclave in which the enclave never recruits, they just get their numbers growing through pro-creation
Like I said, Bethesda can make something up. They can have you start out as a member of the Enclave like they made you a member of the Brotherhood in Broken Steel of Tactics. Then there will be like options in which you can either stay with the Enclave or defect from their ranks. I don't see that happening in the future any time soon - if at all.
This is great. The frayed edges are great for capturing the feel of an old worn poster you'd see mounted on the ruined walls of the Wasteland, and the framing of the helmet, shoulders, and general bulk of the armor while still having room for the ominous pointing hand is very imposing. Plus, the pose and text is a great throw-back to the old Uncle Sam posters of American history, which works even greater in the context of the Enclave.