I GREW UP IN LAKE CHARLES, LA., WHERE WE FISHED AND hunted, living off the land. Like many others, I went to work for the petrochemical industry and stayed for years. That’s where the jobs were. But in 1994 my company offered a buyout. I left and started pushing the chemical industry to clean up its pollution and treat people fairly. I also tried to convince oil companies to explore alternative energy supplies.

Progress was difficult. Fossil fuels were cheap. The underlying principle of the American economy was this: the more fossil fuels we consumed, the richer we became.

The situation is strikingly different today. Spiraling oil and coal consumption drains the economy, depletes the environment, puts America at the mercy of oil-rich states that don’t like us, and weakens the middle class. Domestic jobs are being lost.

Some economists predict trouble, but others see a once-in-a-lifetime opportunity to change how we propel the nation. High fuel prices? Scale up cellulosic ethanol plants. Soaring electricity rates? Retrofit older buildings and construct new ones that are more energy-efficient. Melting glaciers? Replace conventional coal-fired power plants with alternative technology.

This green economy is already unfolding. Production of renewable energy systems is the fastest-growing industrial sector in the world; revenues are rising 25 to 40 percent a year.

What’s more, the clean energy, conservation and efficiency sectors are employing hundreds of thousands of workers. Green-collar job creation is starting to replace the 4.1 million blue-collar jobs the nation has lost since 1998, according to the U.S. Department of Labor. Green-collar jobs—installers, line workers, electricians, pipe fitters, and many others—pay wages capable of supporting families and producing careers.

The wind industry alone now employs nearly 20,000 Americans. Newton, Iowa, which lost 1,800 washing-machine manufacturing jobs in 2006, has replaced more than a third of them with two new plants that produce blades and towers for wind power companies. More than 25,000 people reportedly work in the U.S. photovoltaics industry. Sharp Electronics has converted a fading Memphis facility to solar panel production and employs nearly 230 union workers earning solid wages.

All of this sounds encouraging. But to make the transition from the old blue-collar economy to a new green-collar economy, the U.S. needs to scale up its capacity to design and build clean energy in ways that encourage suppliers and users. If the nation wants to supplant Germany, China, Spain, Japan and Denmark and really lead these robust new energy markets, federal and state governments must establish new investment policies that aid entrepreneurs, new tax and credit rules that provide financial incentives, new funds for research and development, and new thinking that quickly shifts our transportation policy away from cars to efficient rapid transit.

The consequences of such a move can be dramatic. In a well-regarded 2004 study, my organization, the Apollo Alliance, showed that a $300-billion investment in the country’s economic and energy future over 10 years would produce 3.3 million jobs. The new principle of American prosperity in the 21st century should be this: clean energy technology that curbs climate change, makes the world more secure, and produces vast new industries and business opportunities can provide the country with millions of good jobs.