One of the main reasons for anger is to demonstration or recover a sense of power. "They did this to me. They have to learn that they cannot treat me like this." It seems so clear. We believe that right and wrong, good and evil exist in watertight compartments. We see those who have provoked our righteous anger as wrong and perhaps even bad, so we have the right to make them suffer. Making the other — or others who have some connection with the main perpetrator of suffering — suffer gives us a sense of satisfaction in having regained power. The determination to get even serves as temporary relief, but the abused becomes the abuser. We need to remember that this projection of blame acts as a defense against having to look inward.
— Christopher Titmuss, Transforming Our Terror