Empty Quiver pretty much had it right. This has nothing to do with morals , upbringing, or video games. Jesus is not going to stop it either. Cain killed Able- ad nauseum. This was a malfunctioning biological unit, made possible by a genetic defect, and triggered by an unknown biological or chemical environmental agent. I have worked in the mental health field for over 20 years, a very high percentage of the people I see have such disorders. This is just like an electrical device, it works every day...... until it does not. When it malfunctions, it may or may not be able to be compensated for, corrected, or shut down. Most are low functioning anyway, but some are at the high end of the spectrum.
We have three options that I see. None are perfect, nor pleasant.
#1 We can eliminate all weapons that enable one person to kill main or injure multiple others, to the point of stone age man. It will not prevent all killings, just lower the body count.
#2 We can permanently incarcerate all persons that have been diagnosed with any mental condition that has a remote correlation to violent acts, place them in physical and /or chemical restraints, and prevent their reproduction if the disorder has any genetically transmittable component, including monitoring for and aborting any fetus's that show genetic markers for the disorders in question.
We do this immediately upon DIAGNOSIS, not waiting for any overt acts.
# 3 We feel extremely sad, sick to our stomachs, nauseous, and either wonder if there is a God-where was he- or wish we believed there might be and he had intervened. We call and check on our kids. If we have friends or loved ones with problems, we do our best to see that they get treatment and take their meds. We pony up extra funds for mental health programs- and then demand that they be spent where they need to be - not on office furniture and executive salaries. We pray, if we believe----and even if we don't--just in case. We jack up school security. We do the best we can. Until it happens again. AND IT WILL.
Then we go through it all again. Because the other options are in the end- much worse.