There has always been an evolution by those who are mentally ill and how they effect "society".  Think of all the spree killers, cult killers and serial killers of the 60's through 80's.  Before that you had more localized nut jobs who would fire bomb a school or some other gathering area.  Before that in the "old West" you had the gangs of psychopaths like Billy the kid that would terrorize areas.

With today's instant news and glorification by the media of any "mass" shooting that isn't gang related in an urban environment it is the go to thing to do for any kind of dysfunctional outcast.  Be it an Islamist or rich white guy with gambling losses or former Airmen Bible studies teacher. 

If your faith in humanity is so depleted that you think a movie or video game makes someone go on a shooting spree I'd say you don't have a grasp on reality.  These people have and always will be amongst us and they will evolve into using/doing new things to disrupt society.  Look at how many are just simply moving into running down dozens/hundreds of people with a truck.  My guess is the next level could very well be using drones to drop explosive devices on large crowds but no one knows what the next step will be until it happens and becomes the next way for these people to make their outbursts.

As for crime in general it really has never been safer, as a whole, in civilized societies.  Just because you feel crime has increased in your minuscule corner of the world doesn't mean it has everywhere or even there.  Remember the media's only role in this world is to keep the masses riled up thinking every day is the worst ever and you must watch them to stay alive and on top of things.