While a natural disaster such as Hurricane Katrina or the tsunami of 2004 can have profound emotional impact on the survivors, there is a uniquely destructive effect from trauma that is caused by other people, specifically if there was intention to cause harm. We are profoundly social animals and a good deal of our psychology is devoted to the negotiation of interpersonal relationships. If we suffer significant harm at the hands of another person, that can throw our entire worldview into doubt. Are people still good? Can other people be trusted? While the loss of a sense of safety regarding our physical surroundings can be enormously frightening, we do not expect morality from the weather. A natural disaster does not in itself threaten our fundamental belief in the decency of humanity. When people lose trust in other people, they can suffer from deep depression and social alienation.