At the onset of the Great Depression, Buffalo had 573,000 inhabitants, making it the 13th-largest city in America. In the 75 years that followed, this once-mighty metropolis lost 55 percent of its population, a decline most dramatic in its blighted inner city but also apparent in its broader metropolitan area, one of the 20 most quickly deteriorating such regions in the nation. Twenty-seven percent of Buffalo’s residents are poor, more than twice the national average. …