National Review, founded by William F. Buckley Jr. in 1955, has had an enormous impact on the nation's politics. Its writers formulated the ideology that animated the quixotic Barry Goldwater campaign of 1964, and then Ronald Reagan's successful run for the White House in 1980. In the years since, National Review has often worked to keep Republican presidents focused on implementing its vision of conservatism, while bucking up the conservative troops when the movement has found itself out of power.

Today the magazine enjoys circulation roughly equivalent to that of The Nation, the American Left's leading journal of opinion, and more than twice that of William Kristol's The Weekly Standard, its primary competition on the Right.

And now, National Review may be fighting for its life.

Climate scientist Michael Mann is suing National Review and Mark Steyn, one of its leading writers, for defamation. It's a charge that's notoriously hard to prove, which is no doubt why the magazine initially refused to apologize for an item on its blog in which Steyn accused Mann of fraud. Steyn also quoted a line by another conservative writer (Rand Simberg) that called Mann "the Jerry Sandusky of climate science, except that instead of molesting children, he has molested and tortured data." (Simberg and the free market think tank for which he works, the Competitive Enterprise Institute, are also named in the suit.)

The lawsuit has not been going well for the magazine. In July, Judge Natalia Combs Greene rejected a motion to dismiss the suit. The defendants appealed, and last week D.C. Superior Court Judge Frederick Weisberg rejected the motion again, opening the door for the discovery phase of the lawsuit to begin.

That's not all. On Christmas Eve, Steyn (who regularly guest hosts Rush Limbaugh's radio show) wrote a blog post in which he excoriated Greene, accusing her of incompetence, stupidity, and obtuseness. As a result of this outburst, the law firm that had been representing National Review and Steyn (Steptoe & Johnson) has dropped Steyn as a client and reportedly has plans to withdraw as counsel for the magazine as well. (Now representing himself in the lawsuit, non-lawyer Steyn continues on the attack here and here.)

[Update: National Review publisher Jack Fowler says that it was Mark Steyn who initiated the break with the law firm of Steptoe & Johnson, not the other way around.]

Now, the lawsuit may well be dismissed down the road. But the longer it continues, the more likely it becomes that Mann will eventually prevail, either by forcing an expensive settlement or by prevailing in court and winning a substantial penalty from the defendants.

It's doubtful that National Review could survive either outcome. Small magazines often lose money and only rarely manage to break even. They certainly don't have substantial legal budgets, let alone cash to cover an expensive payout. Indeed, in 2005, Buckley said the magazine had lost $25 million over 50 years.

I certainly wouldn't cheer the demise of National Review (and not just because I wrote a handful of book reviews for the magazine over a decade ago). Aside from its historic importance, the magazine continues to employ several gifted writers (among them Ramesh Ponnuru) who foster thoughtful discussion of policy and ideology on the Right. Its contribution to that conversation would be missed.

At the same time, there is something fitting about the magazine's predicament. National Review once devoted itself to raising the tone of conservative intellectual discourse. As part of this civilizing mission, its founding editor summarily excommunicated the paranoid cranks of the John Birch Society from the conservative movement. He also spent 33 years hosting an erudite talk show in which leading intellectuals and public figures from all points on the political spectrum debated important issues of the day.

The ideological descendants of the Birchers have since taken their revenge. Today they are the conservative movement's most passionate supporters and foot soldiers. But they demand a steady diet of red meat, and National Review now exists in part to provide it.

Hence the career and reckless writings of Mark Steyn, a man of considerable polemical talent who specializes in whipping right-wing readers into a froth of know-nothing indignation. That he decided to impugn a scientist's research and reputation on the basis of little more than convictions rooted in the magazine's ideological agenda isn't surprising at all.

What is surprising is that this same magazine has now been placed in jeopardy because Steyn did his job a little too well.