The proximity of Friday’s mass shooting in Aurora, Co., to the site of the 1999 Columbine High School massacre less than 15 miles away raises a question of whether violence occurs in clusters? Slate.com says violent episodes seem to cluster in space, time, and type of target. Antiviolence programs like Ceasefire and the Violence Prevention Alliance compare violence to disease because it proves contagious–one act of violence often begets another, and because it moves in epidemic-like cycles.
Violence can manifest in acute outbreaks—genocides, gang wars, class riots—or in long-term patterns of aggressive behavior. Studies report that those who suffer abuse as children may carry the latent “illness” for years before visiting symptoms upon their own kids. Violence perpetuates itself when we observe it happening or when we experience it ourselves. Nancy Guerra and L.R. Huesmann have reported ways in which brutality against partners and children can lead to violence against acquaintances and strangers, and eventually to widespread violence in a community.