I was reading a very interesting article here, which argues that the theme and reason for the popularity of much modern music, including a lot of the violent stuff, is that it speaks to a culture of parental abandonment.
Here are some quotes:
The odd truth about contemporary teenage music — the characteristic that most separates it from what has gone before — is its compulsive insistence on the damage wrought by broken homes, family dysfunction, checked-out parents, and (especially) absent fathers.
This is the sound of one generation reproaching another — only this time, it’s the scorned, world-weary children telling off their narcissistic, irresponsible parents, ...[Divorce] could be rock’s ideal subject matter. These are songs about the chasm in understanding between parents — who routinely don’t comprehend the grief their children are feeling — and children who don’t know why their parents have torn up their world.
(Hat tip to Richard England.)