Upheavals of the Machine Age

There's a new book out, The Second Machine Age, that takes a penetrating look at how technology has affected modern American life. Although American wealth has generally increased over the course of our nation's history, so far, the peak year for inflation-adjusted American household income was 1999. The median household income that year reached $54,932.

By 2011, though, that figure had fallen to $50,054 per household, a drop of nearly 10 percent. Over that same time frame, though, GDP and productivity were increasing. The increasingly automated economy has hit the middle class particularly hard.

The other side of this is the top of the economic pyramid is getting wealthier. In 2012, the top 10 percent of Americans earned more than half the nation's income. That's the first time that had happened since before the Great Depression.