This type of thing makes me sick too. The strange thing is, if you look at the rates of violent crime over that last 30 years, they are steadily declining. I'll try to find some evidence to back that up, but I heard it recently on NPR.
It seems that the ones we do hear about are horrible. I read an interesting book last year that discussed the notion of FEAR and how a government, whether formal or not, uses FEAR for control of it's citizens. Who is the number one supplier of fear and shock stories and can-you-top-this video footage? The media. The book also mentioned the media as a prime tool, albeit not always knowingly, of governments for spreading the fear they need for control.
Sorry about the tangent. I'll try to find a link...