Another global warming skeptic has dared speak up. Meteorologist John Coleman, founder of the Weather Channel, calls global warming "the greatest scam in history".

"Environmental extremists, notable politicians among them create this wild 'scientific' scenario of the civilization threatening environmental consequences from Global Warming unless we adhere to their radical agenda. I have read dozens of scientific papers. I have talked with numerous scientists. There is no runaway climate change. The impact of humans on climate is not catastrophic. Our planet is not in peril. In time, a decade or two, the outrageous scam will be obvious."

I suspect he's right.

But what if he's wrong?

I've argued that even if global warming is something to worry about, it's dangerous to look to government to fix the climate. Government is a blunt instrument, riddled with self-serving politics and special-interest pandering. To expect it to do something as complicated as calibrate regulations and taxes to fine-tune the climate -- without making many people poorer and a few cronies richer -- is naive.

But that doesn't mean we can do nothing. We have a powerful generator of solutions if we let it work: the free market.

The market has solved environmental problems many times in the past. Before the automobile, America's cities suffered from a terrible pollutant. It bred disease and emitted noxious odors.

It was horse manure.

As economist Nobel laureate Robert Fogel said, "There were 200,000 horses in New York City at the beginning of the 20th century defecating everywhere. When you walked around you were breathing pulverized horse manure". From such air and water pollution, people contracted cholera, typhoid and other deadly diseases.

When the internal-combustion engine came along, the air and ground became much cleaner. Environmentalists romanticize the days before the car, but who wants to go back to that filth and disease? Continued...