I like to spare him so he can cope and seethe about me choosing to be a wandering one man warband out for myself rather than everyone's errand boy. I nuked Megaton because I could. Everyone in Paradise Falls knows I'm in charge when present. When I annihilated what was left of the Enclave, I artilleried the Brotherhood of Steel so there'd be no one left who could oppose me. Nothing is stopping me from rallying the various raider bands and scattered settlements into my personal kingdom. Knowing the path to The Pitt and already being trusted, I can sabotage and assassinate Ashur. I'll have a means of mass producing equipment and ammunition.