The result is a contest of questioned motives. In the conservative view, the real liberal goal is to undermine free markets and national sovereignty (through international environmental agreements). In the liberal view, the real conservative goal is to conduct a war on science and defend fossil fuel interests. On the margin of each movement, the critique is accurate, supplying partisans with plenty of ammunition.

No cause has been more effectively sabotaged by its political advocates. Climate scientists, in my experience, are generally careful, well-intentioned and confused to be at the center of a global controversy. Investigations of hacked e-mails have revealed evidence of frustration — and perhaps of fudging but not of fraud. It is their political defenders who often discredit their work through hyperbole and arrogance. As environmental writer Michael Shellenberger points out, “The rise in the number of Americans telling pollsters that news of global warming was being exaggerated began virtually concurrently with the release of Al Gore’s movie, ‘An Inconvenient Truth.’”

The resistance of many conservatives to arguments about climate disruption is magnified by class and religion. Tea Party types are predisposed to question self-important elites. Evangelicals have long been suspicious of secular science, which has traditionally been suspicious of religious influence. Among some groups, skepticism about global warming has become a symbol of social identity — the cultural equivalent of a gun rack or an ichthus.

But however interesting this sociology may be, it has nothing to do with the science at issue.