This widening gulf between the haves and have-nots has been a consistent trend for a generation or more. Economists largely agree about the primary underlying reasons. New technology has made many jobs obsolete, while creating dramatic opportunities for wealth in computers, finance, and media and entertainment. Global competition has done the same. As middle-class assembly-line jobs vanish, and routine white-collar work gets outsourced overseas, the value of education and special skills rises. The power of unions continues to decline.
For people in the broad middle class, the economic picture over the past decade has been mixed. Unemployment has been low and inflation largely contained. But behind those reassuring trends, you'll find a lot of volatility in labor markets — what economists call "churn." In short, there's more hiring and firing going on.
That churn had led to new opportunities for many workers, but caused hardship and anxiety for many others. Add to this the fast-rising cost of health care and the decline of employer-paid pensions, and you understand why many middle-class families describe themselves as financially squeezed. Low-income Americans, of course, are financially squeezed as well, only more so.