Under the title, "Asking the wrong question on global climate change", Todd Zywicki turns the question of whether we should Do Something upside down to see what falls out.

Is it true that the only way to "justify doing nothing about global warming now is to deliberatly muddle the science"? I think the answer is quite plainly "no." Even if it is true that global warming is occurring, this is only the first of many questions regarding whether we can justify doing nothing about global warming.

There are several dots that remain unconnected, even if we stipulate that global warming is both occurring, and man-made. To examine the effect of not connecting these dots, let's turn the question of causation upside-down.

...continued in full post...

First, assume that the Earth were warming for wholly natural causes, and that the effect was as dire as the worst-case predictions under the current scenario--the apocalyptic stories we read of famine, pestilence, and natural disaster. Would the fact that this warming were "natural" make any difference at all with respect to whether we should do anything? The answer seems obviously no. We never stand by and simply permit wholesale disaster simply because the cause of the disaster is natural.

OK, if we don't ignore something, present or impending, merely because its cause is natural, it doesn't follow that we must do something about something merely because we caused it.

To imply that if the science shows we are changing the climate we must do something about it is as wrongheaded as it would be to say that if we are not contributing to global warming we should not do anything about it.

And his basic conclusion:

So the real question to ask here is whether on net, the costs of doing something about global climate change outweigh the benefits of doing it.

Ultimately, the issue has to come down to... what is the effect of a warmer climate? If we decide we don't like the effect, what is the best way of changing the trend? Is there some better way to deal with a changed climate?