In a provocative new study, Northwestern University economist Robert Gordon argues that the U.S. may face a century of economic stagnation. Why? Because the productivity increases stemming from three industrial revolutions—steam, electricity and internal combustion, Internet—are now played out. And if that is not bad enough, Gordon identifies six "headwinds" that will further stall American economic growth, e.g., an aging population, a faltering educational system, rising income inequality, competition from globalization, stifling regulations, and the overhang of massive government and consumer debt. Reason Science Correspondent Ronald Bailey thinks that Gordon's crystal ball is a bit too cloudy.