The media is encouraging it in the sense that, every time one of these stories is reported, it habituates the populace to this type of behavior. It
desensitizes the populace to violence such as this in the same way that video games do (go ahead, flame on...but it's the truth) and therefore makes
it seem more "normal" as a reaction to disappointment or anger. Also, energy has to go somewhere and reports of this behavior encourage it as an
acceptable outlet for agression when societal tension spikes.
These events enter into our collective consciousness and become a meme. Behavior and ideas are contagious throughout society.
meme central

The breakthrough in memetics is in extending Darwinian evolution to culture. There are several exciting conclusions from doing that, one of which
is the ability to predict that ideas will spread not because they are "good ideas", but because they contain "good memes" such as danger, food and
sex that push our evolutionary buttons and force us to pay attention to them.
[edit on 15/2/08 by kosmicjack]