Sorry, but you've got the wrong impression of the 'city' due to the bizarro nature of St. Louis, Rolfe. ....
Actually, it wasn't St. Louis I was talking about, but the "town" quixotecoyote mentioned.
I had to go take care of a traffic ticket in a rural Missouri town, population <1000 and there were 3 armed officers there.
I don't think we have three policemen on duty at one time in the whole of our village, population about 1,400, and covering a district of quite a few square miles with a lot of small villages and hamlets, total population about 4,000. And those we have would not be carrying guns, and I think it unlikely that they even have access to guns.
And the idea that I'd see them guarding any civic gathering place is simply off the radar. Traffic control duty is about all you'd see them appear for, if that was necessary. (I was always used to seeing the cops out for our Armistice Day service in the village where I was born, but that's because the war memorial fronted a main trunk road they had to keep closed for 15 minutes. Last year, with the memorial here beside the village green, no cops were needed.)
The village where I lived in England grew to 10,000 people, and it still only had an intermittently-manned police office, locked most of the time, with opening hours posted outside and an emergency telephone by the door.
I find the idea of three armed police routinely on duty at any civic facility in a village of less than a thousand inhabitants quite bizarre.
Nearly as bizarre as having to name my 1,400-strong village as my "city" when buying my NWO Kitty sweatshirt from the US!
Rolfe.