The arts are the default scapegoat in any debate concerning violence, particularly youth violence. Film, television, and video games are only the latest "causes". Before audiovisual technology was embraced by society many forms of literature were thought to breed malcontent and a perverse desire to destroy. Yet millions of people watch violent movies, play violent video games, and read James Joyce. Does this mean that we are all, at the very core, delinquent and violent animals standing on the precipice of a psychotic episode?
We'll start with a word: predisposition. What predisposes a person to violence? This raises a possible nature vs. nurture argument, but let's say it's a little of both. If a person is predisposed to violence they will be attracted to games and entertainment that exemplify conduct to which they identify. They want to engage in violence, but society prohibits them, so they play a game that allows them to engage in the kind of conduct they fantasize about.
While a predisposed person may take certain queues from games due to a lack of creativity, it is nave to blame the game. Being "exposed" to violence is no different than being "exposed" to the nightly news. Horrible things happen, and young people will inevitably be exposed because society is itself violent. Exposure is irrelevantthe only important issue is the ability to distinguish right from wrong. Absent a mental defect, the only reason a person wouldn't know right from wrong is due to bad parenting.
Frequently it is the guilty party who is most vocal against the scapegoat. That is almost ALWAYS the case when it comes to violence. Parents do not want to point the finger at themselves. They do not want to blame the child. The fact that they never blame the child is often part of the problem. If your child understands things like accountability, punishment, and consequence, they probably won't be inclined to body slam their 4 year old little sister.
Do not presume that your child is too young to understand. If they are old enough to own and operate an expensive piece of equipment like an X-Box 360 or a PS3, they are certainly able to understand something as simple as accountability and consequence. Punish your child every once in a while when he misbehaves. Tell him why he is being punished, and explain why he is in the wrong.
If your child is predisposed to violence at an early age, seek professional help. If you don't know that your child is predisposed, you need to pay better attention to the health and well-being of your child. The people who engage in violence don't do it because of a video game. They do it because they have psychological problem and require treatment, or they were simply never taught that violence was wrong.