In 1999, a golfer named Payne Stewart and crew were rendered unconscious by a loss of cabin pressure and their private jet crashed when it ran out of fuel. What does this have to do with the fiscal cliff? Read on.

Even in 1999, one could puzzle over why controllers on the ground couldn't take command of a plane and bring it down safely. Technology certainly existed to make such a thing possible. Yet today we're skipping right past pilotless airliners in anticipation of self-driving cars.

Why? Because we're old. Technological innovation is less miraculous than it seems: It responds to need, and we're an aging country with more people who need help and fewer people to do the helping, including driving us around.

All this was once foreseen by Alan Greenspan, the Federal Reserve chairman in the 1990s, who pointed out a corollary to the giant unfunded long-term liabilities of Social Security and Medicare. Not only does an aging population mean fewer workers to pay for the oldsters' benefits. It means fewer workers to actually produce the goods and services that idle oldsters will want to consume. The corollary to an entitlement-spending crisis is, by definition, a labor shortage.

Robots are coming because robots are needed. In 2013, we can already see the appetite in the transportation sector. Aviation analyst Kit Darby figures the industry will need 65,000 new pilots in the next eight years to cover expected retirements. One reason for the millions Google has been spending to develop a driverless car is to meet anticipated market demand from America's growing elderly population.