The equation in their minds is essentially power == good. They want power over you, and over us, so that they can use this power to do good -- for the quite large set of human beings they feel themselves the protectors of (pretty much anyone but a "straight white dude").
No one has really found a limit on how much power they want, or how much good they think they can do. What we do know is: when you feed them, they get hungrier.