- Decline of religion/spirituality is more pronounced in usa.
- More dual working parent homes (due to free labor markets). I also suspect that while real incomes have risen, actual disposable income has decreased, which pressures households into dual working arrangements. This means less time invested by parents in kids.
- institutional rot of public education . As some poster said, school bureaucracy is now defacto enabler of bullying - by doing nothing when observed... and punishing teachers that actually try.
- the internet has cracked the authority of social groups, with more time spent online and people more fractured among niche interests. This means less oversight and more activities happening without a concerted response by the group
I think you are gonna need to specify what countries you think are worth comparing, because there's not really a structured correlation between the lists you link (and among large countries, the US has relatively high religiosity and relatively low atheism, look above and below at your [1]).
Are drugs a serious factor in the US? In the case of this shooter, his mother was struggling with drugs, had a fraught relationship with the son and the grandmother was pushing them out. Growing up amongst that would build a lot of anger in someone.
- Decline of religion/spirituality is more pronounced in usa.
- More dual working parent homes (due to free labor markets). I also suspect that while real incomes have risen, actual disposable income has decreased, which pressures households into dual working arrangements. This means less time invested by parents in kids.
- institutional rot of public education . As some poster said, school bureaucracy is now defacto enabler of bullying - by doing nothing when observed... and punishing teachers that actually try.
- the internet has cracked the authority of social groups, with more time spent online and people more fractured among niche interests. This means less oversight and more activities happening without a concerted response by the group