The vast majority of people who own firearms are in no way in favor of gun violence. But the fact is that gun laws have not kept weapons out of the hands of criminals in the areas in which they have been passed. Washington DC long had a hand gun ban and was known as "the murder capitol of the USA". Chicago IL and Oak Park IL have enacted hand gun bans and have faced an escalating wave of hand gun violence since.
Virginia Tech was a "gun free zone". Didn't prevent or deter Cho from chaining the front door of Norris Hall shut and calmly walking from room to room killing 32 people and wounding many others, while some teachers bravely attempted to barricade the doors of their classrooms and were shot by Cho through the doors. But if one of those instructors had been allowed to have a weapon (appropriately stored) in their classroom, many lives could have been saved.
You see your post makes sense, one of the few that does. Here or nearby about four years ago a student walked into his school and gunned down the Vice Principal. Believe he wounded a couple of more before being subdued. Again the nutcase knew because of the restrictions that he could walk in and do what the voices in his head told him to do. By the way the Vice Principal was a retired Army LtCol. Imagine surviving 20 years in the Army and then being gunned down by a kid who doesn't like his mommy.
The Sullivan Law has done no good in NY, other than do disarm honest people. The Mob, be it the Westies, Mafia, Russians or the various Spanish speaking gangsters are very well armed.
Politicans want to appear to be doing something, so they pass another law. Law adbiding citizens reluctantly comply. The criminals and the wackjobs do not, that is why they are criminals and whackjobs.

