I'd say there are a number of angles from which to tackle the gun violence problem, but this would surely be one of them. Plus, worth dealing with independent of guns anyway. I wonder if there are links (including inverse relationships) between depression/isolation and classroom sizes or intensity of curriculum or single-sex schools. High school puts hormonal teenagers in a competitive environment every week day for hours; not everyone will cope well with that crucible.

Is there a stronger element of the individual and individual glory/success/achievement in the US than other countries that might explain the narcissism?