Most police departments in the United Kingdom use the 9 Principles of Policing (authorship attributed to Robert Peel without evidence). It is about policing by consent. In the United States, many police departments have been moving towards the military model in dress and equipment. In many minority communities, the police look more like an occupying army.
In Consent, Policing, and School Safety the differences between police in the two countries is contrasted. As the post author says about a frequent appearence of police, “They were dressed for war—not to serve and protect.” US police kill 15 times as many people per capita as the next developed country and 20 times the third. This is not serving the nation, the population, or the police well.
Most of the point are things I had read here and there. Seeing it all in one place made it clear this is policy to move away from. The heavy gun ownership in the US (more than one per person) makes change difficult.