Also in Slate, Troy Patterson sizes up Obama’s appearance on Mythbusters.

It is no secret that the ranks of scientists and engineers in the United States include dismal numbers of Hispanics and African-Americans, but few have remarked about another significantly underrepresented group: Republicans.

No, this is not the punch line of a joke. A Pew Research Center Poll from July 2009 showed that only around 6 percent of U.S. scientists are Republicans; 55 percent are Democrats, 32 percent are independent, and the rest “don’t know” their affiliation.

This immense imbalance has political consequences. When President Obama appears Wednesday on Discovery Channel’s Mythbusters (9 p.m. ET), he will be there not just to encourage youngsters to do their science homework but also to reinforce the idea that Democrats are the party of science and rationality. And why not? Most scientists are already on his side. Imagine if George W. Bush had tried such a stunt—every major newspaper in the country would have run an op-ed piece by some Nobel Prize winner asking how the guy who prohibited stem-cell research and denied climate change could have the gall to appear on a program that extols the power of scientific thinking.

Yet, partisan politics aside, why should it matter that there are so few Republican scientists? After all, it’s the scientific facts that matter, and facts aren’t blue or red.

Well, that’s not quite right. Consider the case of climate change, of which beliefs are astonishingly polarized according to party affiliation and ideology. A March 2010 Gallup poll showed that 66 percent of Democrats (and 74 percent of liberals) say the effects of global warming are already occurring, as opposed to 31 percent of Republicans. Does that mean that Democrats are more than twice as likely to accept and understand the scientific truth of the matter? And that Republicans are dominated by scientifically illiterate yahoos and corporate shills willing to sacrifice the planet for short-term economic and political gain?

Or could it be that disagreements over climate change are essentially political—and that science is just carried along for the ride? For 20 years, evidence about global warming has been directly and explicitly linked to a set of policy responses demanding international governance regimes, large-scale social engineering, and the redistribution of wealth. These are the sort of things that most Democrats welcome, and most Republicans hate. No wonder the Republicans are suspicious of the science.

Think about it: The results of climate science, delivered by scientists who are overwhelmingly Democratic, are used over a period of decades to advance a political agenda that happens to align precisely with the ideological preferences of Democrats. Coincidence—or causation? Now this would be a good case for Mythbusters.

During the Bush administration, Democrats discovered that they could score political points by accusing Bush of being anti-science. In the process, they seem to have convinced themselves that they are the keepers of the Enlightenment spirit, and that those who disagree with them on issues like climate change are fundamentally irrational. Meanwhile, many Republicans have come to believe that mainstream science is corrupted by ideology and amounts to no more than politics by another name. Attracted to fringe scientists like the small and vocal group of climate skeptics, Republicans appear to be alienated from a mainstream scientific community that by and large doesn’t share their political beliefs. The climate debacle is only the most conspicuous example of these debilitating tendencies, which play out in issues as diverse as nuclear waste disposal, protection of endangered species, and regulation of pharmaceuticals.

How would a more politically diverse scientific community improve this situation? First, it could foster greater confidence among Republican politicians about the legitimacy of mainstream science. Second, it would cultivate more informed, creative, and challenging debates about the policy implications of scientific knowledge. This could help keep difficult problems like climate change from getting prematurely straitjacketed by ideology. A more politically diverse scientific community would, overall, support a healthier relationship between science and politics.

American society has long tended toward pragmatism, with a great deal of respect for the value and legitimacy not just of scientific facts, but of scientists themselves. For example, survey data show that the scientific community enjoys the trust of 90 percent of Americans—more than for any other institution, including the Supreme Court and the military. Yet this exceptional status could well be forfeit in the escalating fervor of national politics, given that most scientists are on one side of the partisan divide. If that public confidence is lost, it would be a huge and perhaps unrecoverable loss for a democratic society.

It doesn’t seem plausible that the dearth of Republican scientists has the same causes as the under-representation of women or minorities in science. I doubt that teachers are telling young Republicans that math is too hard for them, as they sometimes do with girls; or that socioeconomic factors are making it difficult for Republican students to succeed in science, as is the case for some ethnic minority groups. The idea of mentorship programs for Republican science students, or scholarship programs to attract Republican students to scientific fields, seems laughable, if delightfully ironic.

Yet there is clearly something going on that is as yet barely acknowledged, let alone understood. As a first step, leaders of the scientific community should be willing to investigate and discuss the issue. They will, of course, be loath to do so because it threatens their most cherished myths of a pure science insulated from dirty partisanship. In lieu of any real effort to understand and grapple with the politics of science, we can expect calls for more “science literacy” as public confidence begins to wane. But the issue here is legitimacy, not literacy. A democratic society needs Republican scientists.

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