It doesn't matter in the least. Now that the Gov't is on record as claiming that human activity causes climate change, it is only a matter of time before it conceeds that something must be done about it.
It is impossible to argue otherwise because the public will not understand the limitations and arguements against doing something. They will demand action.
It might not happen during Bush's term but I wouldn't be surprised if it does.
I frankly have no idea what is going to happen...