I don't think 2 is true, except maybe in the sense that the bar for "mass murder" is going down (e.g., shooting 2 people is now a mass shooting).

Of course, I don't think 3 is necessarily true either; there is some evidence that the deterrent effect from personal use of guns - e.g., pointing a gun at a home invader and telling him to get out - may prevent more violence than the presence of guns causes.