In 1978, Ed Koch assumed control of a city plagued by filth, crime, bankruptcy, and racial tensions. By the end of his mayoral run in 1989 and despite the Wall Street crash of 1987, his administration had begun rebuilding neighborhoods and infrastructure. Unlike many American cities, Koch's New York was growing, not shrinking. Gentrification brought new businesses to neglected corners and converted low-end rental housing to coops and condos. Nevertheless, not all the changes were positive--AIDS, crime, homelessness, and violent racial conflict increased, marking a time of great, if somewhat...