You build infrastructure when you expect to grow, because that's when infrastructure creates the most value. Chicago during the late 19th and early 20th century wast he fastest growing city in the world, and was becoming wealthy from its central location in transcontinental trade.

Today, nearly all traditional American cities are on the tail end of a long decline (save a small handful, like New York, San Francisco, and Seattle), or else are the kind of sprawly suburban cities that don't have the same need for the ambitious public works that the traditional, dense, American cities had.