How do your suburbs make your city what it is?

For all the talk we get into here on how large our cities are, it is metropolitan population that is a far more salient statistic in what makes a city tick than the city's own population. All the acolades that we pour on cities like San Francisco or Boston that manage to be so major, so vibrant, and yet so small are meaningless if we don't consider the huge size of the Bay Area and metropolitan Boston. So why not examine our cities by looking at their suburbs, too. Those suburbs are separated from the city by little more than an arbitrary city limits. Under then municipal services, there is no real distinction between the city and the towns that abut it. Let's talk about your city. What contributions do your suburbs make due to their size or their offerings that largely impact the nature of your city itself, the beneficiary (or the victim) of the suburbs that surround it? Does LA, as a city, benefit by having Disneyland, the Rose Bowl, Rodeo Drive, Malibu, the Santa Monica pier in its surroundings? How influenced is Detroit as a city by the attitudes of subrban Detroiters to it? Can you really understand DC if you do not understand VA and MD? Is part of what makes us take Miami so seriously lie on the beaches that run from Miami Beach to perhaps as far north as Palm Beach? Does Dallas's money and power get muted if you don't look at north Dallas, beyond city limits or to University Park (SMU), Irving (Cowboys), Arlington (Rangers)? Are Clayton's high rises park of what makes St. Louis work the way it does? Is Marin's mellowness and Silicon Valley's technology integral parts of what makes San Francisco tick? Can even mighty New York City be fully understood without getting an understanding of the Jersey towns and cities on the Hudson's west bank?>