The problem in the USA is a social issue, not guns. There are many more asshats in the USA now than previous decades and something needs to be done about that. Other than the occasional random shooting, most of it is gang related and confined the liberal meccas of DC, Chicago, LA, NYC, Detroit, etc. The poor and uneducated are mostly to blame, so lets fix that. Personally, a law forbidding the idolization of gangstas (be it rap music, advertising or anything else) would go much farther to fix things.
There was a period of time where kids in the rifle club took their guns on the school bus so they could go shooting after school. No big deal. Now making a gun out of your fingers and saying "pew pew" as kids play at recess gets you expelled. 'Seems this heavy handed approach isn't working. Big Brother approaches never do.