youre not wrong in that there are parts of the united states that are mini war zones, and disarming the police wouldnt make sense. but those are outliers. its a huuge country and youre talkin <1% of officers. lets make exemptions where needed.
there is no "united states police", and so we have 50 tiny countries each with their own versions (city,county,state) of different kinds of police forces, and barely any of it is coordinated or standardized.