Cops have been militarized pretty heavily, in the US
I think you may be thinking of SWAT teams, but those teams are only deployed in situations like bank robberies, hostage situations, school shootings, etc and they do not regularly patrol, do proactive surveillance.
My municipality got M16s from this Pentagon program some years ago, and at least some of the officers were actually pissed because it replaced the shotgun they used to carry and which was actually useful because it could load breaching shells to blow open doors, which was its most common use.
By military uniforms, I mean, like, fatigues? Drab green, no colors. CPD insignia.
That's not true and is the reason people are upset. Nobody disagrees with the use of SWAT teams for school shooting and the like. However, that isn't how militarized units are used in real life. There simply isn't enough violent crime in most areas to justify a full time force dedicated to it. Instead, SWAT is used to target drug offenses (often times w/o an indication that there will be violence). In fact, the federal 1033 program (which funnels military hardware to the police) was founded to help fight the war on drugs.
The other big use of SWAT is for search warrants where they have replaced patrol officers in 80% of cases, the vast majority of which don't involve any suspicion that things will get violent.
https://www.motherjones.com/politics/2015/08/new-documents-r...
Today, vests and semi autos are by far the norm.
"NBC 5 checked with more than 114 police departments in the Dallas-Fort Worth area. Out of 79 responses, it was discovered only one Plano officer still carried a revolver."
https://www.nbcdfw.com/news/local/last-revolvers-retired-as-...