[However, a]ll you have to do is glance at American politics to see how widely faith and reason can be separated. Evolution denial is a basic example of how faith and reason become mutually exclusive, and it is a tenet of at least two of the leading Republican presidential candidates. Once you can accept anything that basic and important to the exclusion of all evidence of the senses and the empirical world, you are lost to reason, at least in the Enlightenment sense of the term. And we live in an Enlightenment world.
I'm a lot more concerned about the candidates' various positions on immigration and health care reform than I am about their (un)informed opinions on evolution.
At which point it occurred to me for the first time that the very obvious connection I see between evolution denial, either of the Creationism or Intelligent Design sort, and deep political trouble, is not necessarily so very obvious to others. Especially to people who aren't committed secularists. So, slightly paraphrased (and edited for clarity), here is my answer to lordofallfools:
As for the candidate's positions, I simply don't trust the reasoning of anyone with the kind of mental block that evolution denial requires. That's faith-based reasoning, not reality-based reasoning. What you get is pretty much the Bush administration. Where, for example, the deep faith in tax cuts means that tax cuts are considered the ideal policy response to literally any economic situation. Where, for example, PNAC's obsession with Iraq, melded with Bush43's daddy issues, means that invading Iraq was going to happen no matter how they had to twist the evidence of WMDs and the 9-11 rhetoric.
To your specific concerns, would a Millennialist view immigration in a sensible fashion? Bush is a Millennialist, Huckabee is almost certainly one. If you believe the End Times are at hand, and coming in your lifetime, how do you manage the long term population and economic issues that immigration presents? Why would you even bother coming up with a sensible solution?
Likewise healthcare. How does someone who believes in healing through prayer view health insurance? How does someone with a religious mandate manage reproductive health? The Bush administration's handling of teen sexual health through abstinence only programs -- faith based reasoning -- has been a massive waste of Federal money with no substantiation other than the belief of his Evangelical constituency. The stem cell ban -- another faith-based bit of reasoning -- has shifted the focus of key elements of biomedical research to Europe and East Asia, which in turn undermines our technological competitiveness and leadership.
Or go back in time, to James Watt, Reagan's Secretary of the Interior, who told Congress that since Jesus was going to return in our lifetimes, we didn't need to make long term plans for resource conservation. (I think it was a timber or coal hearing, don't recall right now.)ETA:ericjamestone points out in comments that there is no primary attribution for this, and the cite cannot be substantiated.
These are the kinds of things that make me think that faith to the exclusion of reason is a very important political disqualifier. The candidate's positions on immigration and healthcare are directly related to their opinions on evolution, because evolution is a key signifier for that constellation of nonrational thinking which disregards actual data in favor of a cherished belief. That is not the basis of public policy. It can't be, not if the United States wants to continue to prosper in a world where our economic and political competitors are led by (generally) rational, empirical actors.
Faith-based reasoning in politics has real, tragic impact on real life. When you have political leaders who begin from a position of faith so blindered to reality as any evolution denialist does, public policy is off the rails before it starts.