Christina Romer, chair of the president’s Council of Economic Advisers, says the reason unemployment remains so painfully high is clear: It’s not the inadequacy or laziness of the workers or the long-standing mismatch between workers’ skills and employers’ needs. It’s the old-fashioned Keynesian diagnosis: Too little demand in the economy.

“The overwhelming weight of the evidence is that the current very high—and very disturbing—levels of overall and long-term unemployment are not a separate, structural problem, but largely a cyclical one. It reflects the fact that we are still feeling the effects of the collapse of demand caused by the crisis. Indeed, at one point I had tentatively titled my talk “It’s Aggregate Demand, Stupid”; but my chief of staff suggested that I find something a tad more dignified,” Ms. Romer said in remarks prepared for a conference at Princeton University today.

It doesn’t have to be this way, she argued, essentially making the case for more government stimulus to help the economy. “We have the tools and the knowledge to counteract a shortfall in aggregate demand. We should be continuing to use them aggressively.” Her comments contrasted with a recent flurry of optimism among some forecasters that the recovery may turn out to be stronger than the lackluster one many anticipated. “We we are growing again, but not booming,” she said. GDP is rising at a solid pace, but not as quickly as after other severe recessions and not as quickly as it needs to. As a result, the unemployment rate remains painfully high and is not predicted to reach normal levels for an extended period.” The jobless rate, at last report, was 9.7%