Removing CFCs from our industry may or may not have been necessary to save the ozone layer.

We do know it was not cost-free.

I'm constantly hearing "err on the side of caution," with long lists of what failing to take action might cause. I rarely see the balance of the costs of taking action.

The numbers vary widely, but I have seen costs worldwide for the changeover from Freon and other similar substances ranging from the hundreds of billions to the trillions of dollars. Things that use refrigeration aren't as cheap any more, and some Third Worlders have been priced out of the new refrigerator markets. Halon is gone, with the exception of special uses. Things in spray cans that didn't used to be flammable before are now. The new refrigerants are harder on machinery than Freon was. Time was a refrigerator would run forever. We'll see how that works out. A lot of things changed, became a bit more difficult, a bit more expensive. It adds up. Nothing is cost-free.

But if the environmentalists turn out to be wrong on something, who pays? Industrialists who put out a product that has lethal flaws are dragged over the coals and sued for billions. To the best of my knowledge, the penalty for scientific error that has been forced into national or international policy is to write a paper that says, "oops."