Not Sure Im Supposed To Be Here

I have a bit of a theory regarding the insane pivot of the BOS between fallout 3 and 4, and it mostly has to do with the Enclave. In 3 the Brotherhood of Steel is this altruistic, good meaning and helpful faction that wishes to do good for most of the capital wasteland.

In Fallout 4, they’ve pivoted HARD into a fascistic Army-state intent on wiping the Commonwealth clean of any and all creatures and factions they consider to be a threat. Why is that?

One could chalk it up to Maxsons reforms and call it quits there, but I believe that the Brotherhoods change in demeanor runs far deeper than just Maxson. I believe that either A: elements of the Enclave infiltrated the BOS after broken steel, or B: Lyons BOS recruited some of them into their ranks.

The evidence is a little flimsy but this is what I’ve got: Danse describes the conflict in the Capital wasteland as a civil war (he could obviously be referring to the Outcasts, but the outcasts were refolded in after Maxson took charge and it would not be unbelievable for former enclave members to create a revisionist history). We also know that shortly after the events of broken steel, the BOS becomes entangled in a war with Super Mutants (who would be particularly useful in a war against these mutants? Enclave personnel, specifically those that worked on project purity). There’s also the fact that the BOS pivoted so hard ideologically from Lyons brotherhood, going so far as to predate on the settlements they once helped, and acting far more like an Enclave contingent rather than, well, the BOS.