A short if very worthwhile article by a Harvard academic, Gene Beresin, MD, who is director of the training program in child psychiatry at Massachusetts General Hospital, about the effects of media violence on children and adolescents. In this article, Beresin lays out the facts rather simply and effectively.
Read the article to understand the actual state of understanding how the research is very clear: The correlation between viewing media violence and children becoming involved in violent acts is not really a controversy. Rather, the issue is figuring out which children are most at risk to move from viewing violence to doing it. Other factors like poverty and family violence certainly play roles in moving kids toward violence.
Further, the sheer number of hours of exposure to violence for kids has grown exponentially over the past 60 years. Half of all children, for instance, have TVs in their bedrooms. Parents do little monitoring of what is watched. Video games move the child from being a passive viewer to becoming an active participant. Desensitization to media violence leads to desensitization to actual violence. Violence is perceived by children as a way to solve problems.
In short, the problem needs to be tackled head on. Beresin proposes that physicians and other professionals working with children work both to educate children and their families to the facts and the concerns and to work with media outlets to make changes in their creations. All of this is quite difficult to do as I have found that parents of kids already prone to aggression often turn a deaf ear to such educational efforts. But such work, both clinical and societal, is crucial. We must see the problem as a public health issue of great import.