I am having trouble connecting any part of this to the actual city of Chicago, in which there are no "heavily secured rich enclaves", and absolutely huge tracts of middle class bungalow-belt housing.

You can drive to Lincolnshire or Kenilworth to see rich-folks compounds, in the suburbs. In Chicago, the white folks in Beverly and Oak Park and Evanston live in nice houses on small lots across the street from rougher neighborhoods. You'll find more metal gates in (rough) Lawndale than you will in (rich) Lincoln Park.

Also, what is this "ring" you're talking about? Can you be more specific?