I disagree. I think radical ideologies, fatherless homes (e.g. broken homes, divorce), big pharma and their minions (doctors) who over-prescribe pharmaceuticals to the American population, boys who are given no guidance on how to become a man and interact successfully with the opposite sex -- I think those things are fundamentally responsible for gun violence.
But as I read in a book about systems: it's a lot more comforting to think that the problem is somewhere "out there", rather than confronting the fact that our system is setting up people to fail.
It's a lot easier to point at guns and say, "let's get these off the streets!", rather than confront the more difficult reality of everything I mentioned.