Rarely in history has the cause of a major economic problem been so clear yet have so few been willing to see it.

The major reason this recovery has been so anemic is not Europe’s debt crisis. It’s not Japan’s tsumami. It’s not Wall Street’s continuing excesses. It’s not, as right-wing economists tell us, because taxes are too high on corporations and the rich, and safety nets are too generous to the needy. It’s not even, as some liberals contend, because the Obama administration hasn’t spent enough on a temporary Keynesian stimulus.

The answer is in front of our faces. It’s because American consumers, whose spending is 70 percent of economic activity, don’t have the dough to buy enough to boost the economy – and they can no longer borrow like they could before the crash of 2008.

If you have any doubt, just take a look at the Survey of Consumer Finances, released Monday by the Federal Reserve. Median family income was $49,600 in 2007. By 2010 it was $45,800 – a drop of 7.7%.

All of the gains from economic growth have been going to the richest 1 percent – who, because they’re so rich, spend no more than half what they take in.

Can I say this any more simply? The earnings of the great American middle class fueled the great American expansion for three decades after World War II. Their relative lack of earnings in more recent years set us up for the great American bust.

Starting around 1980, globalization and automation began exerting downward pressure on median wages. Employers began busting unions in order to make more profits. And increasingly deregulated financial markets began taking over the real economy.

The result was slower wage growth for most households. Women surged into paid work in order to prop up family incomes – which helped for a ...