With the economy stagnating and unemployment high, where are the jobs of the future going to come from? A few years ago, it seemed as though the Green Economy could be a big part of the answer.

New clean-energy sources could address environmental, economic and national security problems all at once. In his 2008 convention speech, Barack Obama promised to create five million green economy jobs. The U.S. Conference of Mayors estimated in April 2009 that green jobs could account for 10 percent of new job growth over the next 30 years.

Alas, it was not to be. The gigantic public investments in green energy may be stimulating innovation and helping the environment. But they are not evidence that the government knows how to create private-sector jobs.

Recently, Aaron Glantz reported in The Times on some of the disappointments. California was awarded $186 million in federal stimulus money to weatherize homes. So far, the program has created the equivalent of only 538 full-time jobs. A $59 million effort to train people for green jobs in California produced only 719 job placements.