Some 40 mayors from around the world are here in Paris for a City Lab conference - a way to network, share ideas and flex the collective muscle of municipal decision-makers. Many on this continent wonder: are identity politics becoming more local? There's a growing rift within those urban areas. As hip and cool city centres become magnets of attraction for those who embrace the new world order, they're also becoming magnets of resentment for all those who live far away from the bright lights. Produced by Daniel BARNEY, Selina SYKES and Christopher DAVIS.