Considering that these 'conservatives' have passed more moderate agenda items then conservative items, it's quite plain to see who they value more. And as they continue this trend, the conservatives will leave the party
So far Bush has made sure we won't be a party to the Kyoto Treaty or the International Criminal Court, he's gotten us out of the U.S. - CCCP ABM Treaty that was preventing the U.S. from deploying our ABM defenses, he's banned using foreign aid money for abortions, pushed through 2 military pay raises and 2 tax cuts for the rest of us, among other things.
Okay, so he's fiscally conservative. Big whoop. What about CFR? Rhetoric in support of AWB? 15 billion for AIDS in Africa? 2 billion for some pipe dream car? These things affect my life more personally and more directly (considering they're coming out of my paycheck and limiting my rights) than some international treaties.
Perhaps there are more people who consider themselves moderate than people who consider themselves conservative? Like it or not, numbers win.
Conservatives may leave the party, but unless there are enough of them to form a competitive third party, they won't win, and they won't get anything accomplished.
I think someone said above that the split in the party is between those who see the glass as half-full and those who see it as half-empty. To mix metaphors, I'm one of those who believes half a loaf is better than none, and none is what we'd get if the liberals were in power.
Right now, we don't have the numbers to obtain the full loaf, and while that's not an ideal situation, it is the reality.