There are 40,000 gun-related deaths in the US annually. 3/4 of those are suicide. Of the remaining 10,000 per year, the vast majority are due to drug-related gang activity. If both of those are removed from the statistics, you'd find more people die falling from ladders and working with hand tools than do from gun violence (justified shootings, mass shootings, robberies, etc). Suicide is illegal. Gang banging is illegal. Thus, people in either of those categories will not care if using a gun (whether obtained legally or not) is used to commit the act.
Waco, TX, which has the highest gun ownership per-capita in the entire US, also has the lowest crime rate. Areas with the most restrictive gun-control laws, conversely, have the highest gun violence levels. Nut jobs that go to kill en mass target "gun-free zones" exclusively. They may be deranged and psychotic, but they're not stupid. Personally, I'd rather my surroundings be well-armed and defended.