Maybe not nationalized, but probably needs to be pulled to a level or two higher than it is. I think Subsidiarity issues come into play.
I live and St. Louis County and we have 90 or municipalities and 60 or so police departments, plus a St. Louis County Police force. And in my experience there is a great difference in quality. Where I am currently sitting, had it's police department disbanded a few years back. I actually don't know at the moment what police department would respond to my 911 call. On my 20 minute drive home from work, I drive through at least 15 municipalities and have no clue who is responsible for what.