Good question. My first answer is psychotherapy. I have repeatedly seen it change myself and others from the diminish-others-to-feel-good-about-yorself position to one where self esteem flows from effort and appreciation of self. BUT I have seen few public or mass attempts to change this behavior that have seemed succesful. I can't think of one now. The cause of this behavior is so deeply personal that I'm not sure general/public campaigns can really adress it. Yet somehow, I feel I'm wrong. Maybe we just haven't tried.