I don't pretend to know whether John McCain really and truly believes that mankind has caused all the temperature increases on earth since 1980. I'm pretty sure he doesn't think that skeptics are "flat earthers" or believers in a faked moon landing like Al Gore does. Nevertheless he'll soon embark on a "global warming tour" (wonder if he'll talk about the PDO?).
But before the veins pop out in your temple consider McCain's long experience at politickin'. Climate change? Sure, he's down with it, dude. Bush screwed up Katrina? Right on, bro--he went down to N'awlins and said "never again, my friend". Illegal aliens? Si, mi amigos. La bienvenida a Los Estados Unidos! Gitmo? Roger on the stand down--bring 'em to Leavenworth. Harsh interrogations? Not gonna be tied up on those again.
He's effectively immunized himself from all those Democrat attack points, leaving only Iraq and tax cuts as his weak spots. But just how weak are they?
Everybody is tired of losing in Iraq but nobody wants to lose a war. Maverick has the harsh blowback from losing in Vietnam seared in his memory. He knows Iraq is much more of a direct threat to our national security than his war ever was, and he'll be working hard to convey that to the voters. The image of choppering-out would stay with everyone, including our enemies, for a long time. So people might support a different leader if they get the drift that a loss might mean our eventual return to the region under even worse conditions. Lebanon is already flaring.
Tax cuts? Well, everyone wants to keep more of their own money. It's an old saw that people vote their wallets and when McCain paints Obama as the biggest liberal to come down the pike since McGovern they'll be grabbing for them.
So, Obama will no doubt hammer away on those two narrow issues while his own political platform will be fair game, with the possible exception of pastor Wright. He knows the reverend will be handled by the 527s and/or Fred Thompson; McCain will complain about it and they'll stop, but the damage will have been done. He's craftier than we think, I think.