Well, you say that, but I could say the opposite just as easily. You don't have to be a fool to believe that there's nothing we can do to prevent or minimize "global warming". It's pretty logical: if you can't prove that we caused "global warming" (and in fact it seems that we did not, IMO), then there's nothing we can do that is the reverse of what supposedly caused it that would have a reverse effect.
The recent rise in temperature is very easily within normal variance. I don't have any particular references to show that, but I know they're out there. Temperature is going up, yes. But no more severely than other stretches of time in very recent history, so the whole notion of "global warming" seems to me to be a ridiculously exaggerated idea that probably started out as a non-serious suggestion by someone who was joking, and it somehow took grip and snowballed to the point where it is now.
As for the quotes posted above by Republican candidates, whether or not they really believe what they said, we will never know. It's politics. "Global warming" is such a huge pseudo-issue that sparks heated debates on par with those regarding abortion that politicians have to play it safe. Such is politics.
We can argue until the cows come home about whether or not we cause "global warming", or whether or not there's anything we can do to prevent or minimize it, but I've said it before, and I'll say it again. We really can't say that "global warming" would be a bad thing overall, even assuming it's a real thing and that we cause it.