Mortality Salience and Violent Feedback
Jesse Bering at Scientific American recently wrote an interesting article about research from Germany showing that those primed to think about death were more likely to be nationalistic. As the article notes,
[T]he evolution of self-consciousness in our human ancestors came with a heavy price, which was the awareness that they were mortal. This awareness of death brought a crippling sense of anxiety... that interfered with our ancestors’ otherwise adaptive, everyday social behaviors. To cope with this anxiety... our species evolved a suite of psychological defenses that allowed us to accept the unavoidable reality of death while assuaging our existential fears and to get on with the business of being alive.... [M]ost people tend to endorse their own prevailing cultural worldviews because culture serves as an anxiety-reducing buffer against thoughts of death. Contribute meaningfully to this system, or at least defend it, and a part of you will live on in the cultural ethos even after you turn to dust.
Once violence erupts in a region, there are many reasons to think about your own death as people you know die or are seriously injured. In these cases, terror management causes us to be hold more in-group tendencies and be more patriotic. This leads to more prejudice and hatred, which leads to more violence, and thus more mortality priming, etc. This is a nasty feedback loop that may be responsible for compounding the initial effects of violence throughout generations.
Yet another reason that we should strive to stop violence between cultural groups before it starts, and be thankful (at least in the US) for our current relatively peaceful society.