This sounds true at face but do we have any evidence that violence per capita is lower here now than it is in a tighter but less organized clan society of yesteryear where any violence you would perpetrate would either be against your own extended family or outside aggressors (and modern society or at least US is already very brutal to outside nations).

On the other hand, also a level of terror unimaginable in the past if you happen to be in the wrong place at the wrong time.