If everybody was armed, trained and confident we would have no need for police as there would be very little crime, legalize all narcotics as well and you have almost no crime at all. Occasionally people would off each other for mere disagreements but it would happen at a very low level.

Ultimately, actually very quickly the population would conform to a "mutual respect society", where guns would rarely need to be used, people would just get along because being a prick or criminal would not he tolerated.