The total number of emergency services personnel in the US are just a drop in the bucket compared to the number of armed and trained citizens.
This is a strong limiting factor to where rioters can riot.
Add to that emergency services personnel can change location to where trouble is brewing.
If your Mayor or local leaders are Republicans you have absolutely nothing to worry about.
If they are Democrats you are totally f&^%ed.
Life is simple when you know the rules.