That’s David Frum’s pitch (disclosure: He’s one of Giuliani’s national security advisors) to get social conservatives to take another look at Rudy.

If Giuliani captures the Republican nomination, it will be precisely because Christian conservatives will have come to the same realization as economic conservatives, national security conservatives, etc.: the guy who cleaned up Times Square, and broke the Mafia, and saved the lives of 1,500 New Yorkers per year, most of them minorities, can do the most to implement a conservative agenda nationwide after 2009.

Some social conservatives have qualms about Giuliani, I know that well. But it’s very wrong to suggest that there is some kind of reciprocated feud on the other side. I think it’s rather more accurate to describe the relationship in the old slogan of the Irish tourist board, as one of friends who haven’t met yet.

First, all of this Rudy speculation may be moot: He’s running a national campaign, and he’s ahead there, but he’s way behind Romney in Iowa and in New Hampshire. If he doesn’t pick up wins or at least compete in the early states, he could still crash and burn, especially if he doesn’t do well in southern states on the super-duper primary schedule.

But supposing he doesn’t and he gets the nomination, I won’t deny that there’s something to Frum’s analysis. Rudy took on the entrenched liberal interests in New York, a city that was nearly written off as ungovernable before his tenure, and won. He took on the press and won. He took on the criminals and the race hustlers and all the other miscreants and troublemakers and won.

I also won’t deny that Giuliani makes for a compelling national security leader. He is the mayor who kicked out Arafat and returned the Saudi donation, and he’s the big city mayor and major political figure who seemed to comprehend the threat of terrorism before most other political figures did. Giuliani’s the quickest and best at refuting Democrat nonsense, meaning he’ll be a formidable opponent for the likes of Hillary Clinton. There’s something about Giuliani’s mayoral career that’s suggestive of Teddy Roosevelt’s brief run as New York’s police commissioner. Well, to me anyway.

So that’s the good. Then there’s the bad, which consists of the obvious breaks between Giuliani and the Republican base’s core social concerns. There’s Giuliani’s consistent record of undermining immigration law and sneering at those of us who favor enforcement. There’s his personal life, his liberalism and along with all of that the possibility that he’ll end up governing more as a liberal Democrat than a conservative Republican regardless of the party label he happens to carry into office. There’s the possibility, which some in the party will think of as a feature rather than a bug, of his ascension marginalizing the socially conservative wing of the party. Before the libertarian wing celebrates that, it ought to consider its ramifications. The social cons are one of the GOP’s more energetic factions; they’re motivated, they vote, they donate and they door knock. The GOP without them may attract more independents temporarily, but it could lose one of its cornerstones in the process.

So what am I saying in all this rambling? Beyond “I’m not sure about Rudy,” well, I’m not sure. Giuliani gives us reasons to think he’ll govern as a tough conservative who’ll win the war, he’s given us reasons to suspect that he’ll govern as a sort of tough liberal who could go in almost any direction, and he has given us reasons to fear that no matter how conservatively he may govern, he’ll derail himself and let us down with some kind of personal scandal.

With all of those scenarios competing for our thoughts, it’s nearly impossible to get enthusiastic about his candidacy, and some social cons will resist it no matter who he’s up against. That by itself is a legitimate reason to question his viability. Maybe Rudy is a social con’s friend. If so, he has some courting and convincing to do yet.