Last week’s Republican primaries in Alabama and Mississippi drew some attention to the nature of politics in the deep, deep south. Particularly notorious was a survey from Public Policy Polling which showed that only 12% of Mississippi Republican voter believe Barack Obama is a Christian, 66% disbelieve in evolution and 29% think interracial marriage should be illegal.

Southerners often feel unfairly put upon and resent being the butt of jokes from the rest of the country. And true enough, there are crazies to be found everywhere. But Matt Steinglass in The Economist explained why we need to keep an eye on this sort of thing:

“… the fact is that higher levels of racial prejudice and resentment in the South are real and politically relevant, and pretending that political contests these days aren’t affected by racial attitudes is a form of deliberate ignorance that warps our political discussions …

“What is driving these voters’ visceral dislike of our biracial president …? What makes them uncomfortable and angry about the direction the country is heading? Who are these voters, what are their worldviews, how are we supposed to understand the messages they’re sending through their votes? … To interpret what you’re looking at when you read the Republican primary results out of these states, these are all things you have to understand.”

In short, southern voters have plenty of reasons to vote against Mitt Romney, who for all his attempts to reinvent himself still looks to them like a northeastern establishment moderate. And since the views that Alabama and Mississippi display in concentrated form are shared by much of the Republican base around the country, it’s no surprise Romney’s path to the nomination hasn’t been as smooth as he would like.

Many commentators, however, have fixed on an additional reason for Romney’s underwhelming performance: the supposed fact that evangelical voters (a large majority among southern Republicans and a significant presence elsewhere) won’t support a Mormon candidate.

It’s true that from the fundamentalist point of view Mormons don’t count as real Christians. But it’s not nearly so obvious that the fundamentalist voters actually care about this sort of theological subtlety.

Andrew Sullivan, one of the strongest defenders of this theory, points to such evidence as an exit poll in South Carolina that “found 57 percent saying it’s very important that a candidate share their religious beliefs” — of whom only 22% voted for Romney. Sullivan concluded: “If you build a political party on sectarian foundations, as the current GOP has been, then you won’t be able to have a Mormon nominee.”

But I think this shows a misunderstanding of how religion in America works. At least on the Right, religion has become an overwhelmingly political matter: as the fundamentalist rapprochement with the Catholic church demonstrates, theology just isn’t important any more.

Kenan Malik put it well earlier this year: “In recent decades, faith has, in other words, transformed itself into the religious wing of identity politics. Religion has, ironically, become secularised, driven less by a search for piety and holiness than for identity and belongingness.” To some extent this is a worldwide trend (Malik is talking particularly about Muslims and blasphemy law), but it’s been especially strong in America, where religion has always had a populist, carnivalesque tinge, eschewing hard questions about doctrine.

The evangelicals don’t like Romney, but what they don’t like is his obvious lack of seriousness about their issues (or indeed anything else much). If you had a Mormon candidate who they were convinced was reliably anti-choice and anti-gay, I suspect the evangelicals would happily vote for them.

Sullivan’s evidence begs the question. He just assumes that by “religious beliefs” those voters mean things like “Mormon vs Baptist (or whatever)”, whereas I think they mean “pro-choice vs anti-choice” and the like. No doubt theology still matters in a few obscure quarters, but for most fundamentalist voters there is no longer a real non-political content to religion. Hatred of liberals, gays and women has ceased to be a consequence of religious belief and has become part of its very essence.

In a sense that’s good news, since it means the end of old-fashioned sectarianism. But what it’s been replaced by is not very attractive, and it’s taking the GOP into some very dark places.