Your character in Fallout New Vegas had only a minor part to play in this episode, but one thing he did-mine that is-was make sure New Vegas was not absorbed by either the NCR or Caesar's Legion. The Brotherhood formed Caesar's Legion to counter the threat. The NCR was becoming too powerful, too advanced. The first real problem for the BOS was the emerging power of the New California Republic.

No doubt other Enclaves in China, Russia, et al, were dealt with in similar ways. The emergence of the Enclave was another problem-blown up by one of your characters in Fallout 2. The Master was a minor problem, mostly dealt with by one of your characters in the original Fallout. For their belief was that technology was what had given Humanity the power to destroy itself to begin with.

What they did first and foremost was seek out old technology of all kinds and remove it from the world. The Brotherhood itself was weak-probably only a few thousand world wide. It was all they could do to survive from one day to the next. The few survivors of the war had no way of forming communities. Therefore the goal of the international BOS was that civilization itself should never arise again. The unbridled lust for power and wealth of the leaders of these civilizations had been the cause of the catastrophe. Their utter belief was that civilization itself was responsible for the nuclear, chemical, and biological war that had just ended. They made contact with other breakaway para military units in Europe, Asia, Australia, Africa, and South America. They operated in complete darkness, and they soon became international. They were fragmented and isolated, but united in their hatred for a civilization that had destroyed most of Humanity. They were traitors to the United States government. The Brotherhood began hours after the start of World War 3.

Fallout 4 destroy brotherhood of steel