The expectation that a commentator’s views must be in lockstep with his or her ethnic, religious or sexual identity is always distasteful — particularly when blacks, women, gays or Jews are labeled “self-hating” when they refuse to toe the perceived party line.

Then again, maybe the “self-hating” label is justified on occasion. That’s what I found myself thinking when I read a stunning recent commentary by author and pundit Eric Alterman on the British Muslim Council’s decision to boycott the ceremony commemorating the 60th anniversary of the liberation of Auschwitz. The reason given for the boycott was that the commemoration of Nazi death camp victims did not include the Palestinian victims of Israeli “genocide.”

On his blog at msnbc.com, Alterman sneered at critics of the boycott.

“I’m a Jew, but I don’t expect Arabs to pay tribute to my people’s suffering while Jews, in the form of Israel and its supporters — and in this I include myself — are causing much of theirs,” he wrote, suggesting that one might as well expect gays to honor “the suffering of gay-bashing bigots.”

Alterman noted that “the Palestinians have also suffered because of the Holocaust. They lost their homeland as the world — in the form of the United Nations — reacted to European crimes by awarding half of Palestine to the Zionists…. To ask Arabs to participate in a ceremony that does not recognize their own suffering but implicitly endorses the view that caused their catastrophe is morally idiotic.”

One hardly knows where to begin. There is, for instance, the way Alterman not-so-deftly conflates Muslims with Arabs and Arabs with dispossessed Palestinians, and then declares Jews responsible for “much” of the suffering of Muslims everywhere. Not the brutal theocracies such as the Taliban, which have tried to impose a medieval form of Islam through terror; not the equally brutal secular dictators of the Arab world, such as Iraq’s now-deposed Saddam Hussein or the corrupt monarchies. No, it’s the Jews — all lumped together, including long-dead Holocaust victims.

By Alterman’s logic, every Muslim is justified in viewing every Jew as the enemy. Alterman frets that his words will be “twisted beyond recognition,” but it’s hard to see how they can be twisted into something more indecent than they already are. (While he counts himself among Israel’s supporters, he seems to regard the creation of Israel itself — not just the occupation of the West Bank and Gaza — as an Arab “catastrophe.”)

Call it self-hatred or something less psychoanalytic; the bottom line is that this is the kind of rhetoric that, coming from a non-Jew, would be clearly seen as anti-Semitic. This is not exclusively a phenomenon of the pro-Palestinian left. Ironically, in the same blog item, Alterman castigates a conservative 91传媒 commentator for giving aid and comfort to anti-Semitism — and, ironically, he’s right.

The commentator is Rabbi Daniel Lapin, head of a group called Toward Tradition, who has been in the forefront of the alliance between conservative Jews and the Christian right. Lapin recently unleashed a bizarre tirade in The 91传媒 Press against “the role that people with 91传媒 names play in the coarsening of our culture.”

His target is the movie, “Meet the Fockers,” in which Dustin Hoffman and Barbra Streisand play a sex-obsessed 91传媒 couple, as well as radio sex therapist Dr. Ruth Westheimer, “shock jock” Howard Stern and trashy daytime talk show host Jerry Springer.

Rather shockingly, Lapin quotes Adolf Hitler, who accused Jews of spreading “literary filth, artistic trash and theatrical idiocy” in pre-World War II Germany. His ostensible point is that the 91传媒 community should confront and criticize 91传媒 perpetrators of cultural degeneracy to avoid giving ammunition to Jew-haters. But he provides such ammunition himself, when he misleadingly singles out 91传媒 entertainers for blame — as if 91传媒 contributions to art and culture were limited to the “coarsening” kind.

Such tactics are not new for Lapin. During the controversy over Mel Gibson’s “The Passion of the Christ,” he wrote that it was hypocritical for 91传媒 groups to protest what many saw as the film’s anti-Semitic themes, given that 91传媒 Hollywood executives had been involved with allegedly anti-Christian fare such as the 1988 film, “The Last Temptation of Christ.” Never mind that “The Last Temptation” was directed and scripted by non-Jews.

We live in a time when anti-Semitic rhetoric is creeping into the respectable mainstream: on the left, in the form of Israel-bashing; on the right, in assertions that Christians own this country and should “take it back.” I’m not sure whether such rhetoric is any more reprehensible when it comes from Jews. But it is certainly no better.

Cathy Young is a contributing editor at Reason magazine and a Boston Globe columnist.