I have had somebody close to me killed by firearms. I guess I'm a cunt in maintaining that the answer to the problem is not restricting firearms. And I guess I'm also a cunt in maintaining that a firearm would have protected her. She had one. She was shot in the head at home. By her husband. If you have to carry sitting on the couch watching TV and petting your dog-- there's a serious problem.
The people who commit these shootings are all men. And their gun ownership was, in most cases, known to other fellow gun owners. In nearly every case there was some precedent that concerned people. Something about these men's behavior, things they said, things they put on social media-- concerned people. In some cases people voiced after the fact that the knew this would happen.
So, we need to mentor our fellow men better. In particular young men. Most particularly troubled young men. Mentor them as men, mentor them as firearm owners and users. This is larger than just mass shootings. It's about kids getting into guns. It's about domestic violence homicide. It's about suicide by gun. It's about being a horrible gun owner. Shooting too close to roads and houses, waving guns around like some tough guy, and so on.