For as long as there have been machines, there have been worries about their power to destroy jobs. The Luddites — early-nineteenth-century artisans who bitterly resisted the new textile machinery that was making them obsolete — are only the most famous example of workers who fought the mechanization of labor. A similar fight has played out many times since the beginning of the Industrial Revolution, over water mills and steam engines, electricity and the assembly line.

But no one today would wish away these technologies. That is because, over time, economies kept growing, jobs were created, wages rose, and prosperity was…