But it’s not just culture. In the twentieth century, American cities were dominated by a narrative of decline in large part because they were actually beset by serious economic decline. This narrative—and reality—lasted so long that many people took it to be simply how things were: American cities were poor, often victimized by racist stigma, and suburbs were rich and racially privileged

As early as the 1920s, the sociologist Harvey Zorbaugh quoted people who swore that time was up for the residents of Tower Town, Chicago’s bohemian answer to New York City’s Greenwich Village, as young artists abandoned it. (Many of those who left just settled a short walk up the lakefront in what we now call Old Town.) Zorbaugh himself was convinced that the Gold Coast, the last inner city stronghold of Chicago’s upper class, had barely ten years left before the rich realized they would have fewer headaches farther from the chaos of the downtown Loop. (A century later, the Gold Coast is still, well, Gold.)

Often, even the gentrifiers themselves don’t quite believe that what they’ve created can last. Into the 1970s—when parts of Lincoln Park had already become wealthier than many white-collar suburbs—a Lincoln Park neighborhood association director fretted that one wrong development might push the area towards a “ghetto.”

Why have we found it so hard to believe that a generations-old trend of growing affluence at the core of a major city could be durable? And why has it proven so durable?

The answer to the first question surely has something to do with the strong American cultural bias that the natural habitat of the middle-class (usually white) person is a suburban single-family home.

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