I think the actual violence committed for whatever reason - invading countries, blowing up weddings and children with remote drone strikes, keeping prisoners without legal framework in gitmo - these things are several orders of magnitude worse than violent games and movies

Games and movies are merely ways of processing these real world events - all violence begets violence. Those kids we blow up today with drones, one of their brothers, sisters, or even just friends will eventually come back to us. For example, to senselessly kill innocent people at a marathon.

Boston bombings are a good example - the chechen war / rebellion was a bloodbath, fought ruthlessly and largely off the cameras. It just came back to us.

Violence begets violence, throughout the history of humanity. Its up to us to stop the cycle. We cant do much about conflicts in faraway countries - except maybe to stay out of them. But we can do things we are directly responsible for - CIA operations come to mind, and of course the drone war.