Since many police forces outside of the US are controlled by the national government, not by local governments, I'm not sure that there is a valid comparison to be made here. While the French Gendarmes, the Italian Carabinieri, and others do have armored vehicles, they tend to be limited to specialized units within the force, like the French Mobile Gendarmes. Here, in the US, there are literally thousands of police forces, varying in size from under a dozen to well over 10,000 (iirc, NYPD has about 25,000 officers). Connecticut, with about 3.3 million people, has about 110 police forces of various types; the forces vary from about a dozen to about 900.