How many Republicans know, for example, that government employment has declined, not risen, under President Obama? Certainly Senator Rand Paul was incredulous when I pointed this out to him on TV last fall. On the contrary, he insisted, “the size of growth of government is enormous under President Obama” — which was completely untrue but was presumably what his sources had told him, knowing that it was what he wanted to hear.

For that, surely, is what the wonk gap is all about. Political conservatism and serious policy analysis can coexist, and there was a time when they did. Back in the 1980s, after all, health experts at Heritage made a good-faith effort to devise a plan for universal health coverage — and what they came up with was the system now known as Obamacare.

But that was then. Modern conservatism has become a sort of cult, very much given to conspiracy theorizing when confronted with inconvenient facts. Liberal policies were supposed to cause hyperinflation, so low measured inflation must reflect statistical fraud; the threat of climate change implies the need for public action, so global warming must be a gigantic scientific hoax. Oh, and Mitt Romney would have won if only he had been a real conservative.