CONSERVATIVES WILL disagree with Alterman, of course. But commentators without any particular ideological ax to grind have their differences as well. Robert Thompson, director of the Center for the Study of Popular Television, at Syracuse University, argues that the liberal-conservative debate is over nuances. "From Fox News to NPR, if you look at all these mainstream mass media, they’re all pretty much hovering around this center," Thompson says. "The media are convenient because they’re a universal recipient of any kind of ire or anxiety that society is experiencing at any particular time."

Jack Shafer, who writes the "Press Box" column for Slate, and who recently wrote a three-part series on bias in the media, finds nothing new to complaints about the conservative media, pointing to A.J. Liebling in the New Yorker of the 1940s, ’50s, and ’60s and Alexander Cockburn in the Village Voice of the 1970s. In fact, Shafer told me that he thinks Hillary Rodman Clinton’s complaints of a "vast right-wing conspiracy" were more credible than the current critique, although he added, "Where I disagree with her was that she thought because there was a conspiracy, that therefore exonerated her husband. He was a perjurer and a serial liar, and she really didn’t have much to complain about."

Shafer also believes that the rightward tilt of the media, and of the culture, over the past several decades is far more the result of vast social change than of media bias per se. He notes that even China has moved to a market economy over the past 20 years, saying, "You can’t blame that on Richard Mellon Scaife."

I think Thompson and Shafer are both right and wrong. Much of the ideological argument today may be over small differences, as Thompson suggests, but Alterman shows how liberal and left commentators who would express much larger differences with the conventional wisdom are kept out of the mainstream media. Shafer is looking at media bias through the prism of ideas, which are anathema to most segments of the media. Bias, at least as practiced by Fox News and Rush Limbaugh, is more about raw partisanship than ideas, and describing how that partisanship works is where Alterman is at his best. Conservatives have clearly gotten the upper hand. Three years ago the media lied about Al Gore "without consequence," to quote Vincent Foster’s comment about the Wall Street Journal editorial page in a note found after Foster committed suicide. Yet when New York Times columnist Paul Krugman, a widely admired economist at Princeton University, simply lays out the lies inherent in Bush’s economic and tax policies, the right brays for Krugman’s head and the mainstream cowers.

"The problem has been very obvious for a long time. It can no longer be ignored," says Joe Conason, a columnist for the New York Observer and a blogger for Salon. "I don’t think reporting of news stories is necessarily influenced by liberal or conservative bias. I do think there’s a serious problem in the commentary media, which of course has taken over so much of the media world. In those new media, such as cable TV and talk radio, where so many people get their opinions formed, there’s a huge imbalance of conservatives."

Bob Somerby is the impresario behind the Daily Howler Web site, which dissects media untruths — such as the claim Gore never made about "inventing" the Internet — with withering sarcasm and argument-ending research. A Harvard roommate of Gore’s who nevertheless points out that he came to Bush’s defense, in 1999, over a series of ridiculous stories about his alleged cocaine use, Somerby told me by e-mail, "I would guess that the claim of liberal bias has by now become so completely absurd that it was inevitable that it would be challenged. After the treatment of Clinton, then Gore, it’s impossible for any sane person to keep arguing that the press corps is somehow driven by liberal bias.... ‘Liberal bias’ is the greatest propaganda tool of the past 40 years — a surefire way to explain away any news report that the right doesn’t like."

And though liberals may finally be fighting back, they’re still losing. Recently, MSNBC canceled its only prime-time show hosted by a liberal, Phil Donahue, even though his admittedly pathetic ratings were nevertheless higher than those of the bellicose Chris Matthews. The latter’s ideological views are hard to pin down, but his anti-Clinton/anti-Gore animus presumably makes him a better bet for the long haul in the eyes of the MSNBC brass. Among Donahue’s last programs was a rollicking hour during which Al Franken eviscerated the so-called facts contained in Bernard Goldberg’s Bias, leaving Goldberg, who was in the studio, to sit and scowl. But Donahue had to go — perhaps, according to a report posted on the Web site AllYourTV.com, because of an internal study that found Donahue’s liberalism made him a "difficult public face for NBC in a time of war" (see "Media Log," BostonPhoenix.com, February 27).

Donahue is expected to be replaced eventually with former Minnesota governor Jesse Ventura. Meanwhile, the latest entry in the right-wing cable-TV sweepstakes is Michael Savage, Allen Ginsberg’s onetime nude-swimming partner (according to a highly entertaining piece in Salon last week) whose nationally syndicated, San Francisco–based radio talk show, Savage Nation, has some six million listeners. Savage’s book, The Savage Nation: Saving America from the Liberal Assault on Our Borders, Language, and Culture (WND Books), released in January, is number two on the current New York Times bestseller list; in a nice irony, Michael Moore’s very liberal Stupid White Men (ReganBooks, 2002) is number one. (Savage is heard in Boston on WRKO Radio, AM 680, Monday through Friday, from 7 to 10 p.m. To learn more about Savage, I recommend MichaelSavageSucks.com.)

Despite protests from the Gay and Lesbian Alliance Against Defamation, Fairness and Accuracy in Reporting, and the Minority Media and Telecommunications Council, Savage brought his brand of right-wing ranting to MSNBC this past Saturday from 5 to 6 p.m. It was Savage Lite, as evidenced by his benign encounter with the presumably lesbian cop. ("I’m not anti-gay. What do they want from me?" he said, smiling, as he signed a copy of his book for her.) Yet he still managed to get in a few of his trademark shots, calling for Bush to seek a declaration of war so that peace activists can be prosecuted for sedition. ("Then we can stop some of these maniacs who are encouraging our enemies, weakening our troops’ resolve, and confusing the American people. What do you think about that?") He indulged his massive ego, referring to The Savage Nation as "a great book" without irony, and telling a caller whose message was "I love your show, Mike": "I don’t blame you. I would love it, too, if I was home watching it." And when a caller tried to challenge his characterization of Mexicans as coming from a "Turd World nation," Savage cut him off.

Recently, on Fox News’s Hannity & Colmes, Savage compared his political philosophy to a National Geographic documentary he’d seen in which a pride of lions rips apart a water buffalo. "When one of the buffalo got pulled out by the lions, they bit the water buffalo in the nose, they bit her in the behind. They started pulling pieces out of her, this beautiful strong animal," he told the co-host, Alan Colmes. "And they could only bring her down by going for her vulnerable parts. And once they got her down on the ground, kaput, it was over, my friend. This country is like a giant water buffalo. We’ve been hit in the nose. They’re going for our anus, they’re going for our vitals. I don’t understand why anybody would want to support the civil liberties of the sleepers in America. That’s who I’m talking about, Alan."

Liberal media bias? You’ve got to be kidding. For more than a generation, the conservatives have been going for — well, our noses, certainly, if not our anuses as well.

Now, finally, liberals are starting to fight back.

Dan Kennedy can be reached at dkennedy[a]phx.com. Read his daily Media Log on BostonPhoenix.com.