National Review's Kevin Williamson argues that nobody should care what Rick Perry or any other elected official thinks about science:

Why would anybody ask a politician about his views on a scientific question? Nobody ever asks what Sarah Palin thinks about dark matter, or what John Boehner thinks about quantum entanglement. (For that matter, I’ve never heard Keith Ellison pressed for his views on evolution.) There are lots of good reasons not to wonder what Rick Perry thinks about scientific questions, foremost amongst them that there are probably fewer than 10,000 people in the United States whose views on disputed questions regarding evolution are worth consulting, and they are not politicians; they are scientists. In reality, of course, the progressive types who want to know politicians’ views on evolution are not asking a scientific question; they are asking a religious and political question, demanding a profession of faith in a particular materialist-secularist worldview.
Progressives like to cloak their policy preferences in the mantle of science, but they do not in fact give a fig about science, which for them is only a vehicle to be ridden to the precise extent that it is convenient. This is why they will ask what makes Rick Perry qualified to disagree with the scientific establishment, but never ask the equally relevant question of what makes Jon Huntsman qualified to agree with it. So long as they are getting the policies they want, they don’t care. 

This actually gets at a profound split between American conservatives and their political opponents. Liberals (and, I'd argue, moderates, but I'll just use the term "liberals" for syntactic clarity) care that a politician believes in climate change and evolution because they believe that elected officials should accept science. Williamson argues that this is because liberals require "a profession of faith in a particular materialist-secularist worldview."

In a sense, that's correct. Conservatives harbor strong philosophical opposition to government. They have practical objections to government as well, but the practical objections are merely layered upon deeper moral beliefs. Conservatives argued that the Clinton tax hikes would impair economic growth, and that the Bush tax cuts would increase growth. Subsequent events made those empirical views very hard to sustain, but conservatives did not even slightly alter their viewpoint. Why? Because their belief in low taxes is, at its core, a belief in the philosophy of small government.

If the Clinton tax hikes actually did massively impair work incentives, cause a recession and reduce tax revenue, liberals would revisit their support for it, because they had no reason to support it save the practical goal of raising revenue at minimal social harm. But the failure of the Bush tax cuts to achieve their purported goal is not a reason for most conservatives to renounce them. They serve a deeper ideological goal.

That does not mean liberalism is right. It just means, as Williamson says, that liberals are naturally more concerned with a belief in science. They want leaders will accept the scientific method and are amenable to data. Conservatives want leaders who are loyal to their philosophy. That's why Perry's stated opposition to evolution and climate science does not hurt him among Republicans, except insofar as they fear it might harm him among swing voters.

Perry's staunch climate skepticism is a way of demonstrating a strong commitment to any reform to mitigate climate change. Williamson argues that the "real" debate is whether "the policies being pushed by Al Gore et al. are wise and intelligent." Well, that is one debate. Another debate is whether we should pursue a different set of policies to fight climate change. It's true, as Williamson argues, that one could accept climate science and argue that doing anything to stem climate change is simply too expensive. Yet this position clearly represents a weaker commitment to the values of the conservative movement than full-out climate science denial. One could argue that the costs of climate change are X and the costs of mitigating climate change are Y. But that's a view that implies that if X rises, or Y falls, perhaps we should consider a different answer. Perry is convincingly demonstrating to the right that he will never make that kind of calculation because he denies the entire empirical basis of climate science.

Likewise, Perry's evolution skepticism signals a strong commitment to conservative values over the conclusions of data and experts. On a deeper level, he is demonstrating social solidarity with conservatives against the intellectual elites they resent. He probably won't have to make a presidential decision on teaching evolution, but his answers to questions about it tell you a great deal about how he would govern.