I guess the hottest year on record and the fact that polar ice caps are melting mean nothing.

And maybe that is so. But can we afford to ignore it??

What would be the harm of instituting measures to cut down on emissions that cause greenhouse gases compared to the possible harm that might result if we don't?

Well, it takes some money out of the pockets of shamelessly rich CEOs and it is Bush's job to cut them as much slack as possible. Hence, in his mind, there isn't global warming and he's the president--so there!