I can empathize with these shooters on some level, especially Adam Lanza since he was most obviously autistic and like me hated religiosity and the general irrationality of normative lifeforms, although I don't agree with just shooting a bunch of children ultimately.
I mean, most of the time my opinion on the mass shooting itself is that considering a lot of normative lifeforms are nothing but harm causing, primitive assholes that are probably a threat anyways, it isn't such a loss they don't exist anymore to torment others, but you never know exactly who is shot (is this person able to change or do they insist on being pro-suffering, hypocritical, delusional morons?) so I can hardly justify just shooting into a crowd of randomly selected individuals and ideally there would then be a more peaceful manner to stop them other than to shoot the extremely dangerous and psychotic neurotypicals, in that sense I'm actually pretty anti-violence, I abhor punishment of all sorts, in principle I'd have to say that taking anything other than the least violent step is bad.