AN APOCRYPHAL tale is told about Henry Ford II showing Walter Reuther, the veteran leader of the United Automobile Workers, around a newly automated car plant. “Walter, how are you going to get those robots to pay your union dues,” gibed the boss of Ford Motor Company. Without skipping a beat, Reuther replied, “Henry, how are you going to get them to buy your cars?”Whether the exchange was true or not is irrelevant. The point was that any increase in productivity required a corresponding increase in the number of consumers capable of buying the product. The original Hen...