Daniel C Dennett
Here is a well-known trajectory: You begin with a heartfelt desire to help other people and the conviction, however well or ill founded, that your guild or club or church is the coalition that can best serve to improve the welfare of others. If times are particularly tough, this conditional stewardship -- I'm doing what's good for the guild because that will be good for everybody -- may be displaced by the narrowest concern for the integrity of the guild itself, and for good reason: if you believe that the institution in question is the best path to goodness, the goal of preserving it for future projects, still unimagined, can be the most rational higher goal you can define. It is a short step from this to losing track of or even forgetting the larger purpose and devoting yourself singlemindedly to furthering the interests of the institution, at whatever costs. A conditional or instrumental allegiance can thus become indistinguishable in practice from a commitment to something "good in itself." A further short step perverts this parochial summum bonum to the more selfish goal of doing whatever it takes to keep yourself at the helm of the institution ("who better than I to lead us to triumph over our adversaries?")
We have all seen this happen many times, and may even have caught ourselves in the act of forgetting just why we wanted to be leaders in the first place.