For years — when questioned about Mitt Romney’s faith — Nancy and I have responded with some version of the following: “He’s running for commander-in-chief, not pastor-in-chief, and his core political values are your core political values.”

What we meant was clear.  Mitt wasn’t going to be spending time as president discussing Joseph Smith or any unique point of Mormon doctrine.  Instead, he was going to concentrate on shared values — supporting life, marriage, and religious liberty, for example — and focus on fixing our economy and defending our country.  These shared values stretch across religious lines and unite more than they divide.  Baptists and Catholics and Mormons may not agree on a number of theological fronts, but they are united in supporting life, supporting marriage, and preserving religious liberty.

Rick Santorum is testing the limits of this formula.  Yes, he shares the same broad political values as Mitt Romney and the other Republican candidates — and no one questions his pro-life credentials — but he’s now doing something that I’m not sure I’ve seen from a mainstream Republican candidate: He’s going beyond the shared values of the Republican coalition to making narrow denominational arguments on hot-button social issues.

Let’s take contraception.  All of the GOP candidates agree that Obama’s HHS mandate, which requires Christian institutions to make free contraceptives (and abortifacients) available to their employees, represents a grotesque violation of religious liberty, but only Rick Santorum says this:

One of the things I will talk about that no President has talked about before is I think the dangers of contraception in this country, the whole sexual libertine idea. Many in the Christian faith have said, “Well, that’s okay. Contraception’s okay.”

It’s not okay because it’s a license to do things in the sexual realm that is counter to how things are supposed to be. They’re supposed to be within marriage, they are supposed to be for purposes that are, yes, conjugal, but also [inaudible], but also procreative. That’s the perfect way that a sexual union should happen. We take any part of that out, we diminish the act. And if you can take one part out that’s not for purposes of procreation, that’s not one of the reasons, then you diminish this very special bond between men and women, so why can’t you take other parts of that out? And all of a sudden, it becomes deconstructed to the point where it’s simply pleasure. And that’s certainly a part of it—and it’s an important part of it, don’t get me wrong—but there’s a lot of things we do for pleasure, and this is special, and it needs to be seen as special.

There’s a lot I agree with in that statement, but there’s a lot that I disagree with as well.  I don’t agree with the Catholic church on the theology of contraception.  I respect the Catholic view, but I don’t agree.  And I certainly don’t want my president wasting his limited political capital picking a theological fight on this issue.

And that’s not all, of course.  He’s talked about the “phony theology” of Barack Obama’s environmentalism, and he’s singled out certain kinds of pre-natal testing as especially offensive.  He’s also essentially written mainline denominations out of the Christian faith.

To be clear, there are ways of contesting radical environmentalism — including the more fanatical elements which (as Senator Santorum rightly noted) value the environment more than people — without making the kinds of arguments I’ve heard from the pulpit.  And you can certainly oppose mandates on free-market and liberty grounds without singling out amniocentesis for particular scorn.  As for the spiritual plight of mainline denominations . . . well, I’m just not sure that’s a matter of presidential concern.  (Nor are such sweeping statements helpful or accurate).

I like Rick Santorum.  He’s been a congressional hero of the pro-life movement, and he’s articulating the connection between the breakdown of the family and persistent economic distress better than anyone else in the race.  He was sounding the alarm on Iran years ago — when no one wanted to hear him.  But he’s on the verge of moving from the good Rick Santorum who won two senate elections as a conservative in a moderate state to bad Rick Santorum whose appeal became increasingly denominational and alienated potential allies.  Bad Rick Santorum seemed almost indifferent to winning over moderates, independents, libertarians, and even social conservatives who didn’t agree with everything he said.  Bad Rick Santorum lost in a landslide in 2006.

A presidential candidate simply cannot win a race (and likely can’t even win an extended primary contest) making in essence pastoral, denominational arguments when more ecumenical values and liberty-based arguments accomplish much the same purpose.

See also Rick Santorum’s Pro-Choice Past