ADAM SMITH would be baffled by microelectronics. When the great economist died in 1790 James Watt’s two-cylinder steam engine passed for the height of technological sophistication. If he recognised the prefix “nano”—a fair bet for a precocious classicist proficient in dead languages by 14—it would be as a derivation of the Greek word for “dwarf”, not as a reference to the billionths of a metre in which modern semiconductors are…