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There need be only three people convinced of the urgent need to take action on global warming, and those three people are Alan Greenspan, Warren Buffett, and Bill Gates.

They need to be so thoroughly convinced that they come out in public and speak loud and long on the need for the entire United States to mobilize itself to put all of its creative energy into action to ameliorate and prepare for the effects of global warming.

Those three all know what a sunk cost is, even if the general public doesn't. It makes no difference whatsoever what caused the warming already in the system.

The point is, what are we going to do about it?