Why does Hambro dissapoint the narrator

The narrator cannot shake the thought of Rinehart even as Hambro speaks of the sacrifice of his members toward the new directives. Hambro is unable to explain why, saying he will learn in time. The narrator sees it as the weak being sacrificed for the strong. He feels that he has played a part similar to Rinehart, only using the people for the Brotherhood's ends. Angered, he asks Hambro where the Brotherhood will stop. He leaves depressed and betrayed, thinking back to the betrayal of Bledsoe and Emerson. He decides to stay with the Brotherhood long enough to settle the scores of Clifton, Tarp, and himself.