My father was a NYPD lieutenant in the 40s, and 50s. He said the militarization of the police forces, which he saw happening after WW2, would create an ‘us against them’ attitude. He always said the best policemen were everyday working class men, like truck drivers.
I have no doubt there are still many good men and women in the various departments. The root problem, however, is the policy that’s facilitating the militarization and those attracted to it.