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So it comes to pass that an estimated 85 percent to 90 percent of affiliated Jews in the 5.9 million-member community are not really Jews at all.

They are, as the Union of Orthodox Rabbis of the U.S. and Canada has declared, "outside of Torah and outside of Judaism."

The union's declaration that most American Jews are, in effect, traif, came as a self-described rallying cry in the latest communal battle over who is a Jew.

The union said it was fighting moves by the Conservative and Reform movements to gain enough legitimacy in Israel to conduct britot, marriages, funerals and other life-cycle ceremonies — and trying to bring "innocent" Jews being taught faux-Judaism back to Torah.

But the union's foray into Jewish identity politics is ill-conceived, an effort that shows little understanding of American Jewish life and is guaranteed to only deepen divisions between Jews.

Unlike other chapters in the "Who Is a Jew?" debate, the union's move has captured front-page headlines in the mainstream U.S. press, first in last Saturday's Los Angeles Times.

But the press coverage is offering a distorted picture of reality, by throwing a once-powerful, now politically moribund group into the heart of a crucial, and complex, dispute.

Even if the union emerges as a player in Jewish communal politics, its contribution to the "Who Is a Jew?" discussion adds nothing new.

Rather, this small group that represents a tiny portion of the Orthodox community is declaring unilaterally that the Conservative and Reform movements are shams. Not a real opening for serious talk.

Conservative and Reform leaders ought not overreact. They should simply move on, fostering existing, mensch-like attempts at intercommunal dialogue.

An Orthodox leader unsympathetic to the union's action called the pronouncement "fighting words." This is one fight worth ignoring.