It's hard to imagine now, but in 1944, six years after Kristallnacht, Lessing J. Rosenwald, president of the American Council for Judaism, felt comfortable equating the Zionist ideal of Jewish statehood with "the concept of a racial state -- the Hitlerian concept." For most of the last century, a principled opposition to Zionism was a mainstream stance within American Judaism.

Even after the foundation of Israel, anti-Zionism was not a particularly heretical position. Assimilated Reform Jews like Rosenwald believed that Judaism should remain a matter of religious rather than political allegiance; the ultra-Orthodox saw Jewish statehood as an impious attempt to "push the hand of God"; and Marxist Jews -- my grandparents among them -- tended to see Zionism, and all nationalisms, as a distraction from the more essential struggle between classes.

To be Jewish, I was raised to believe, meant understanding oneself as a member of a tribe that over and over had been cast out, mistreated, slaughtered. Millenniums of oppression that preceded it did not entitle us to a homeland or a right to self-defense that superseded anyone else's. If they offered us anything exceptional, it was a perspective on oppression and an obligation born of the prophetic tradition: to act on behalf of the oppressed and to cry out at the oppressor.

For the last several decades, though, it has been all but impossible to cry out against the Israeli state without being smeared as an anti-Semite, or worse. To question not just Israel's actions, but the Zionist tenets on which the state is founded, has for too long been regarded an almost unspeakable blasphemy.

Yet it is no longer possible to believe with an honest conscience that the deplorable conditions in which Palestinians live and die in Gaza and the West Bank come as the result of specific policies, leaders or parties on either side of the impasse. The problem is fundamental: Founding a modern state on a single ethnic or religious identity in a territory that is ethnically and religiously diverse leads inexorably either to politics of exclusion (think of the 139-square-mile prison camp that Gaza has become) or to wholesale ethnic cleansing. Put simply, the problem is Zionism.

It has been argued that Zionism is an anachronism, a leftover ideology from the era of 19th century romantic nationalisms wedged uncomfortably into 21st century geopolitics. But Zionism is not merely outdated. Even before 1948, one of its basic oversights was readily apparent: the presence of Palestinians in Palestine. That led some of the most prominent Jewish thinkers of the last century, many of them Zionists, to balk at the idea of Jewish statehood. The Brit Shalom movement -- founded in 1925 and supported at various times by Martin Buber, Hannah Arendt and Gershom Scholem -- argued for a secular, binational state in Palestine in which Jews and Arabs would be accorded equal status. Their concerns were both moral and pragmatic. The establishment of a Jewish state, Buber feared, would mean "premeditated national suicide."

The fate Buber foresaw is upon us: a nation that has lived in a state of war for decades, a quarter-million Arab citizens with second-class status and more than 5 million Palestinians deprived of the most basic political and human rights. If two decades ago comparisons to the South African apartheid system felt like hyperbole, they now feel charitable. The white South African regime, for all its crimes, never attacked the Bantustans with anything like the destructive power Israel visited on Gaza in December and January, when nearly1,300 Palestinians were killed, one-third of them children.

Israeli policies have rendered the once apparently inevitable two-state solution less and less feasible. Years of Israeli settlement construction in the West Bank and East Jerusalem have methodically diminished the viability of a Palestinian state. Israel's new prime minister, Benjamin Netanyahu, has even refused to endorse the idea of an independent Palestinian state, which suggests an immediate future of more of the same: more settlements, more punitive assaults.

All of this has led to a revival of the Brit Shalom idea of a single, secular binational state in which Jews and Arabs have equal political rights. The obstacles are, of course, enormous. They include not just a powerful Israeli attachment to the idea of an exclusively Jewish state, but its Palestinian analogue: Hamas' ideal of Islamic rule. Both sides would have to find assurance that their security was guaranteed. What precise shape such a state would take -- a strict, vote-by-vote democracy or a more complex federalist system -- would involve years of painful negotiation, wiser leaders than now exist and an uncompromising commitment from the rest of the world, particularly from the United States.

Meanwhile, the characterization of anti-Zionism as an "epidemic" more dangerous than anti-Semitism reveals only the unsustainability of the position into which Israel's apologists have been forced. Faced with international condemnation, they seek to limit the discourse, to erect walls that delineate what can and can't be said.

It's not working. Opposing Zionism is neither anti-Semitic nor particularly radical. It requires only that we take our own values seriously and no longer, as the book of Amos has it, "turn justice into wormwood and hurl righteousness to the ground."

Establishing a secular, pluralist, democratic government in Israel and Palestine would of course mean the abandonment of the Zionist dream. It might also mean the only salvation for the Jewish ideals of justice that date back to Jeremiah.

Ben Ehrenreich is the author of the novel "The Suitors."