In recent years, socialism—the ideology that gave birth to some of the worst horrors of the 20th century—has made a comeback. Only 30 years after it was consigned to an unlamented grave with the fall of the Berlin Wall, it is making its political return.

Part of this surge in sympathy for socialism is due to Bernie Sanders’ presidential candidacy, as well as the notoriety gained by one of his greatest supporters: Rep. Alexandria Ocasio-Cortez (D-N.Y.), who, like the Vermont senator, is an avowed socialist.

A poll taken earlier this year by Gallup showed that some four in 10 Americans embraced some form of socialism. While a majority of those polled—51%—said that socialism would be a bad thing for the country, a staggering 43% said it would be a good thing.

It’s not clear if those who tell pollsters they like socialism understand what they are saying. Some may just like Sanders or AOC, hate President Trump or view it as a catchall phrase expressing very liberal views about a variety of subjects or antagonism toward big business. But whatever it means, there’s no doubt that the stigma attached to socialism during the struggle against communism during the Cold War and the historical record of what happens when Socialists take over nations has faded.

The irony about this is that, as scholar Ruth Wisse noted in a brilliant lecture given at the third annual conference on Jews and conservatism—an event sponsored by the Jewish Leadership Conference and supported by the Tikvah Foundation—“Jewish socialism” is dead. By that, Wisse, who is arguably the greatest living authority on Yiddish literature, as well as a formidable and insightful commentator on Jewish history and politics, was describing something that is largely extinct.

Prior to World War II and the Holocaust, supporters of the Socialist Bund Party were not merely ubiquitous in Jewish life, but more numerous than Zionists in many places. Jewish socialists won the political allegiances of many Jews who saw in Marxism an escape from both economic misery and religious prejudice.

Yet those hopes—both in terms of the endemic economic failure of socialist systems and the promise of equal rights for Jews—were ultimately dashed by the success of the revolution in Russia. The same is true elsewhere in places where the extreme left has subsequently gained power, as events in Cuba and Venezuela subsequently proved.

Jewish socialists didn’t wish to abandon their Jewish identities. They dreamed of a world in which Yiddish-speaking Jews would exercise a degree of autonomy and nurture their unique culture, in which capitalism would be routed and replaced with a more just system.

But what they discovered was that there was a profound contradiction between the promises of socialism for Jews and what it delivered. In a system built on compulsion and where governments could dictate behavior to their subjects, Jews inevitably found themselves being victimized and told to give up their separate identity.

The only place where Jewish socialism succeeded, at least for a time, was in Israel, where the power of the institutions it created helped build the state. It did not, however, have the same tyrannical impact of other socialist systems. Even there, such ideas were ultimately no match for the genius of the market economy. Still, the contrast between the kibbutzim in their heyday and collective farming elsewhere was that Jews were free to leave and not compelled to become state serfs.

The point about socialism that today’s enthusiasts forget is how closely it is linked to the worst tragedies of the last century. It’s hard for people to admit that the evidence shows that it did far more harm than good. Governments are needed to help those who fall through the cracks of systems rooted in economic freedom, but giving the state so much power inevitably leads to tyranny. And that is something that’s always bad for the Jews.

But the point about Wisse’s autopsy on socialism is that its legacy is antithetical to Jewish interests. Sanders embodies the irony that the man who stands a chance of becoming the nation’s first Jewish or socialist president is someone who gave up the practice of Judaism and is not supportive of Israel. Nor is it irrelevant to point out that the greatest enemies of Israel and the most blatant purveyors of anti-Semitism in our political system, like AOC’s fellow “Squad” members Reps. Ilhan Omar (D-Minn.) and Rashida Tlaib (D-Mich.), have endorsed him. Neither is the choice of left-wing academic elites in the West to support an anti-Semitic movement like BDS a mere accident of history.

If in the past anti-Semitism was derided by some on the left as the “socialism of fools,” Wisse rightly noted that socialism has now become “the anti-Semitism of the enlightened.” The death of Jewish socialism and an honest look at how totalitarianism sprung from its bosom is a warning from history that Jewish communities everywhere can’t afford to ignore.

Jonathan S. Tobin is editor in chief of JNS—Jewish News Syndicate. Follow him on Twitter at: @jonathans_tobin.