I think society has failed them. Addressing guns is not addressing the violence/apathy/mental health, only reinforcing the cycle of sociopathy taking root.
Which is where the core of the argument comes in.
Its a percentages thing.
Will you be able to prevent all of 'sociopathy taking root'? (No.)
What is the damage that can be caused by one person 'going awry'? (Depends.) (Depends even on factors like 'killing with a gun' might seem more 'clinical' (I push trigger, something falls over). Also depends on how many bullets per second fly out of a gun)
If you cant prevent incidence from happening, what would be a good way to mitigate (lower) the number of victims.
Notice, that this isnt just an objective argument, where you would go for victim numbers, but that also aspects like - the families of the deceased do better if they have the perception that most things possible have been done, to prevent such an incident.
(In that sense, I'm not at all sure, if 'giving everyone guns to stop 'em early' would help
).
But the more straightforward argument to make is 'look at the numbers', if there are obvious groups to compare them to, like 'states in europe' - where victims of gun rampages are lower by a factor, so are gun related deaths.
At which point, some people tend to realize (sometimes even intuitively), that its not about actual numbers. Its about a generalized perception of what people are willing to look over as "being an incident" (not preventable). Because thats at the root of taking political action.
And if the entire thing is a rather rare occurence (compared to population size), you can make people simply not think about it. By telling them, there are more important things to do, than to protest.
So in some sense, the 'comparatively high death toll (factor higher than europe)' doesnt matter.
What matters at that stage is 'whats your idealized version/Image' of society. And idealized to a point, that people address conceptual goals, that might only help a minority (people at the receiving end of gun violence). Which is usually not how people function (whats in it for me, or my community).
And at that point (what do I get out of it), we also have to talk about stuff, like 'endorphin rushes' when I shoot, the feeling of power over others, when I carry, my mental image, that I'm sheriff of town, when I carry - because my life might be pretty desolate otherwise, tales, of actually having power, for 15 minutes - in a situation where it was appropriate, in someones life, where they might not experience anything like that ever --
and the link, of that to rampages in the first place ('I want them dead, all they ever did was hurting me.. - and they got somewhere in life...').
The result of all that contemplation - even (almost
) objectively comes down to 'reduce access to automatic weapons' to mitigate issue. If mitigation is your goal. (Kind of a morals question.)
But. You are going against people that use guns as 'power prostheses' in their lives. You are going against 'absolutists' (morals), that can tell you 'if that person had a gun, they could have been alive' (probably not - but thats not the point, you cant counter this argument on an individual level, because in one case, or another they are right -- but as a society, you tend not to optimize for eventualities in rare cases, you want to do something that in the end doesnt end up at a 50:50 chance.
).
And even from a 'subset of society' view, you are going against people, that were told in the military, to shoot the enemy - and who you are now telling, that part of the culture that allows them to deal with it (guns as tools very much a part of their self image), might have to be dismantled, and the 'importance' of gun culture reduced all together.
At which point manufacturers and the NRA interject, and add PR.
The entire 'but we have to keep them for our fight against the government' argument, if they do stuff, that isnt right. Pretty much is romanticized BS, but then its storytelling, so part of the PR.