It really shouldn't suprise people that some neighborhoods in the US are some of the most dangerous in the world. Our own government has created a culture where crime flourishes. The prohibition economy (drugs & other contraband), added to the otherwise relaxed 'security measures' a free society must have, invites wholesale crime and corruption as demand is fed outside the grace of the government.
The nanny statists (socialists), have used this fact to further their agenda of complete government control and power over the citizenry. In their dream environment, where one must ask the government permission before even cutting a tree down, you can imagine what they think of individuals owning weapons. After all, the state is not served by that! Since they are not that strong yet, 'sporting purposes' is the current mantra. In time, the socialists would eliminate the 'sporting' (a ban on hunting, target shooting, etc...) and thus even these weapons would no longer serve a societal purpose (wink, wink).