IMO guns are bad and shouldn't be used for anything other than protection; the "fun" people have shooting a gun is a worthy sacrifice and doesn't really matter. They can have fun other ways. As for carrying one for personal protection; I believe that argument is BS, as the assailant will almost always get the jump on you. They'd have to be stupid not to. Also, any weapon you own can and will be used against you if they can get their hands on it.
However, just because that's my opinion on guns, I do not think the way to go is banning them. As has been stated many times, people will get a gun whether it's legal or not. They're all over the black market these days. Even if they weren't, these people would try to massacre others in other ways such as homemade bombs and things of that nature. It's not going to stop the psychos doing this stuff if you guys change the gun laws. I also don't think most people for the "carrying a gun for protection" or "for sport" argument are the ones committing these crimes, so it's not a huge deal to me that they can own one legally. (Though if you hunt for sport you've lost my respect.)
There's no real solution to this problem other than seeing the warning signs as a parent, or friend, of the killers in question and taking it out from the roots. I think as a society North America needs to take the psychological issue behind these shootings more seriously. Mental illness such as this can, obviously, harm more than just the person suffering. There should be times where the person in question, if they are threatening harm and are serious about it, should be forced into treatment or confinement. Like I said though, it's case-by-case and I think that there should be plenty of steps taken before getting to that point. For example if your kid is a recluse who keeps mentioning his hatred for the world and is obsessed with guns you should make a judgement call on whether to get more people involved or not, instead of pretending that they're normal. Ofc shootings happen that are caused by adults as well, but the same goes for if it's your buddy, or another family member.
Tl'dr: The shootings are caused by people and illness, not weaponry. Banning guns would be arbitrary.