In January, at a symposium at UCLA (choreographed by the Center for Near East Studies), four longtime Israel bashers were invited to analyze the human rights conditions in Gaza, and used the stage to attack the legitimacy of Zionism and its vision of a two-state solution for Israel and the Palestinians.

They criminalized Israel's existence, distorted its motives and maligned its character, its birth, even its conception. At one point, the excited audience reportedly chanted "Zionism is Nazism" and worse.

Jewish leaders condemned this hate-fest as a dangerous invitation to anti-Semitic hysteria, and pointed to the chilling effect it had on UCLA students and faculty on a campus known for its open and civil atmosphere. The organizers, some of them Jewish, took refuge in "academic freedom" and the argument that anti-Zionism is not anti-Semitism.

I fully support this mantra, not because it exonerates anti-Zionists from charges of anti-Semitism but because the distinction helps us focus attention on the discriminatory, immoral and more dangerous character of anti-Zionism.

Anti-Zionism rejects the very notion that Jews are a nation -- a collective bonded by a common history -- and, accordingly, denies Jews the right to self-determination in their historical birthplace. It seeks the dismantling of the Jewish nation-state: Israel.

Anti-Zionism earns its discriminatory character by denying the Jewish people what it grants to other historically bonded collectives (e.g. French, Spanish, Palestinians), namely, the right to nationhood, self-determination and legitimate coexistence with other indigenous claimants.

Anti-Semitism rejects Jews as equal members of the human race; anti-Zionism rejects Israel as an equal member in the family of nations.

Are Jews a nation? Some philosophers would argue Jews are a nation first and religion second. Indeed, the narrative of Exodus and the vision of the impending journey to the land of Canaan were etched in the minds of the Jewish people before they received the Torah at Mt. Sinai. But, philosophy aside, the unshaken conviction in their eventual repatriation to the birthplace of their history has been the engine behind Jewish endurance and hopes throughout their turbulent journey that started with the Roman expulsion in AD 70.

More important, shared history, not religion, is today the primary uniting force behind the secular, multiethnic society of Israel. The majority of its members do not practice religious laws and do not believe in divine supervision or the afterlife. The same applies to American Jewry, which is likewise largely secular. Identification with a common historical ethos, culminating in the reestablishment of the state of Israel, is the central bond of Jewish collectivity in America.

There are of course Jews who are non-Zionists and even anti-Zionists. The ultra-Orthodox cult of Neturei Karta and the leftist cult of Noam Chomsky are notable examples. The former rejects any earthly attempt to interfere with God's messianic plan, while the latter abhors all forms of nationalism, especially successful ones.

There are also Jews who find it difficult to defend their identity against the growing viciousness of anti-Israel propaganda, and eventually hide, disown or denounce their historical roots in favor of social acceptance and other expediencies.

But these are marginal minorities at best; the vital tissues of Jewish identity today feed on Jewish history and its natural derivatives -- the state of Israel, its struggle for survival, its cultural and scientific achievements and its relentless drive for peace.

Given this understanding of Jewish nationhood, anti-Zionism is in many ways more dangerous than anti-Semitism.

First, anti-Zionism targets the most vulnerable part of the Jewish people, namely, the Jewish population of Israel, whose physical safety and personal dignity depend crucially on maintaining Israel's sovereignty. Put bluntly, the anti-Zionist plan to do away with Israel condemns 5 1/2 million human beings, mostly refugees or children of refugees, to eternal defenselessness in a region where genocidal designs are not uncommon.

Secondly, modern society has developed antibodies against anti-Semitism but not against anti-Zionism. Today, anti-Semitic stereotypes evoke revulsion in most people of conscience, while anti-Zionist rhetoric has become a mark of academic sophistication and social acceptance in certain extreme yet vocal circles of U.S. academia and media elite. Anti-Zionism disguises itself in the cloak of political debate, exempt from sensitivities and rules of civility that govern inter-religious discourse, to attack the most cherished symbol of Jewish identity.

Finally, anti-Zionist rhetoric is a stab in the back to the Israeli peace camp, which overwhelmingly stands for a two-state solution. It also gives credence to enemies of coexistence who claim that the eventual elimination of Israel is the hidden agenda of every Palestinian.

It is anti-Zionism, then, not anti-Semitism that poses a more dangerous threat to lives, historical justice and the prospects of peace in the Middle East.

Judea Pearl is a professor at UCLA and the president of the Daniel Pearl Foundation.