Violent media may inure people to violence a tiny bit but that's it. The world has always been a violent place and always will be. Remove all the violent media and replace it with sunshine and rainbows and their will still be violence. You want to put a major dent in it then end poverty. That's the only thing that makes a real difference.
“There is no such thing as a weird human being. It’s just that some people require more understanding than others.” - Tom Robbins