Poverty,poor education and easy access to guns are the problem in major cities.This nations right wing gun and social polices are the biggest cause for that imo.
Other wealthy nations don't have the gun,education,healthcare ,wealth inequality and for the rich polices The US has so they don't have the crime and gun violence The US has,even in thier inner cities.
I personally feel you aren't putting any (certainly not enough) blame on the degradation of the family unit. Absent or no fathers is a big part of it.