A few years ago, I barely knew the name Norman Finkelstein. I was vaguely aware of his screed, The Holocaust Industry, which argued that Jews "fabricated" their victimhood. I had heard of his comparisons of Israel to Nazi Germany. ("[I] can't imagine why Israel's apologists ... would be offended by a comparison with the Gestapo," he once wrote.) And I had caught wind that neo-Nazi Holocaust-deniers like Ernst Zundel, now in an Austrian prison, praised him for "making three-fourths of our argument--and making it effectively." But I certainly never imagined meeting such a person.

Like David Duke, who is now teaching in the Ukraine, Finkelstein is a failed academic. By his own account, he has been fired by "every school in New York," including Brooklyn College and NYU. One of his former department chairs attributed Finkelstein's firing to "incompetence," "mental instability," and "abuse" of students with different politics from his own. That may help explain why he accepted a job at DePaul, a school Finkelstein describes as "a third-rate Catholic University." With a political science department known as hard left, Finkelstein finally saw a path toward tenure--a sorry possibility now being debated, and one that I may have inadvertently helped along.

While I was touring in 2003 for my book The Case for Israel, I was invited by Amy Goodman of Democracy Now to debate Noam Chomsky. I agreed, but, when I showed up, it was Finkelstein in the studio. "Chomsky couldn't make it, so we have a substitute," Goodman said. Unbelievably, Finkelstein's performance sunk well below Chomskian standards of honesty. He accused me of not having written or "read" my own book, which he implied was written by Israeli agents. For good measure, he also accused me of plagiarizing it from a 1984 book written by Joan Peters. (His absurd accusation was that I found quotes from Mark Twain and others in Peters's book and attributed them to the original authors rather than to Peters.) Finkelstein knew that, as an academic, I would have to rebut these charges. I asked Harvard to investigate them, which it did and dismissed. Yet Finkelstein continued to repeat his lies--and I kept responding.

Now Finkelstein could say that we were in a feud--a charge that, in retrospect, clearly served his purposes. He published an article in the online newsletter Counterpunch titled "Should Alan Dershowitz Target Himself for Assassination?" An accompanying cartoon portrayed me as masturbating while viewing images of dead Lebanese civilians on a TV set labeled "israel peep show." The cartoonist, solicited by Finkelstein, had won second place in an Iranian Holocaust-denial cartoon contest. To reinforce his point, Finkelstein called me a "moral pervert" who "missed the climatic scene of his little peep show."

Should I have taken his bait? Well, I responded and handed him a crucial argument: Finkelstein could then use our feud to argue that "outside interference" had denied him tenure. His problems, of course, have nothing do with ignorant arguments (he accused Leon Uris of naming his Exodus protagonist Ari, "[a] diminutive of Aryan," reflecting Israel's "admiration" for Nazism) or overt anti-Semitism (he compared Jewish leaders to "stereotypes straight out of Der Sturmer"--the Nazi propaganda organ). In light of Finkelstein's history of attacking Holocaust survivors--Elie Wiesel, he claims, lied about his background--it is not surprising that, when the Iranians convened a Holocaust-denial conference last year, they invited two Americans: David Duke and Norman Finkelstein. (Finkelstein backed out because of a disagreement over his allotted speaking time.)

In our recent contretemps, I can say for a fact that I wasn't provoked into attacking--I was invited. Specifically, the former chair of the DePaul political science department asked me to "point [him] to the clearest and most egregious instances of dishonesty on Finkelstein's part." I responded with evidence of Finkelstein's history of making up quotes, citations, and facts. Despite this evidence, DePaul's politicized political science department voted nine to three to recommend tenure. The dean, however, rejected its recommendation.

And now, just as I could have predicted, Finkelstein screams "outside interference." Naturally, when pressing this case, he presents thousands of signatures from outsiders demanding that the dean reverse his recommendation. He has now organized a "Finkelstein solidarity committee" and threatened a lawsuit. (I can't wait to be called as a witness.) I've been a leading villain of this effort. Chomsky has accused me of launching a "jihad." (I am not alone, it should be noted, in opposing Finkelstein's tenure: The president of the Catholic League for Religious and Civil Rights argues, "Finkelstein lacked the requisites associated with academic excellence.") Chomsky, referring to my involvement, complains that he had "never seen anything like it." Well, I have. Back in the late '70s, Chomsky, who was teaching at MIT, led his own jihad against Henry Kissinger when Columbia University considered offering him a position. Kissinger, of course, was a distinguished academic with a long record of publications, while Finkelstein writes unscholarly ad hominem screeds. But, for Chomsky, that distinction doesn't matter. In his eyes, hard-left politics are enough to qualify an academic as a "good scholar," a term he has used to describe Ward Churchill ("little Eichmanns"), Robert Faurisson (a French Holocaust-denier), and Norman Finkelstein. Great company!

In the past months, I have received threatening calls and letters. The Rutgers biologist Robert Trivers, for one, has warned, "Nazi-like apologists as [you] need to be confronted directly." Suddenly I'm the Nazi? And a masturbating one to boot! I'm not shy about entering arguments, but I can't help feeling like I walked into a trap. How could I not argue against Finkelstein? But, when I raise my voice, I know that I'm supplying essential ammunition. I guess when you've got no scholarship to make your tenure case, you need all the outside interference you can get.

Alan Dershowitz is the Felix Frankfurter professor of law at Harvard and author of Preemption: A Knife That Cuts Both Ways.

Copyright 2007, The New Republic