The markets are anxious. There's every sign that the world's investors have grown nervous about the continued ability of the American consumer to keep the economy perking along. Companies that sell big-ticket items are floundering: General Motors reported a $1.1 billion quarterly loss yesterday. Conversely, drug and utility stocks are doing all right; companies that rely on nondiscretionary spending remain a safe bet.

Part of the problem is that gas prices are siphoning off a bigger share than usual of Americans' incomes. But the bigger problem is that Americans' incomes are stuck or even in mild decline. Though the economy grew by 4.4 percent last year and added 2.2 million jobs, real wages fell by 0.9 percent. The last time U.S. wages fell was in the recession year of 1991. Now they're falling in the middle of a recovery.

Time was when wage increases tracked gains in productivity and profitability -- but that time is long gone. Since 2001 yearly productivity growth has averaged 4.1 percent, while wages and benefits have grown on average by just 1.5 percent. No longer does a rising tide, as John Kennedy famously pronounced, lift all boats. We are now in the 11th quarter of the current recovery.