It might be hard to remember these days, but not so very long ago, the city of Chicago was a study in urban blight, rampant crime, and classic big-city stagnation. So what changed in the Second City between the bad old days of the 1980s and today, when Chicago is held up as a shining example of the Great American Metropolis? Much of the city’s turnaround can be traced to the arrival in office of a mayor who was determined to rebuild the city as a cultural destination, and more specifically, as the theater capital of America.