Do any modern antecedents (you mentioned Sarajevo and Beiruit) have the sort of suburban sprawl we have here in the U.S.? We have a lot of situations where one “side” is concentrated in those built up cities, and the other surrounds them geographically in spread-out suburbs. While I’ve never been to either of those places, from my travel in Europe, it’s a very different built environment in general.
I think that the cities in the USA are so varied by geography, terrain, ethnicity etc that you can find almost any situation, and sureley many dynamics from Beirut and Sarajevo would be repeated.
You seriously don’t want to be in a highrise across from buildings inhabited by your enemies, for example. That is just a built in sniper gallery.