https://quadrant.org.au/magazine/from-our-archives/how-the-left-became-anti-semitic/
Robert Wistrich’s latest work, From Ambivalence to Betrayal, defines Zionism as a national liberation movement. Marx pre-dated Zionism but the analytical tools he bequeathed to his ideological successors predisposed them to sneer at the concept of Jewish national self-determination as a petty-bourgeois folly. Consequently, Kautsky, Luxemburg, Lenin and Trotsky all derided Zionism, and yet Wistrich accuses none of these icons of the Old Left of being overtly anti-Semitic: catastrophically wrongheaded, yes; but anti-Semitic, no. Wistrich has far less sympathy for the anti-Zionist Left of today. Its impenitent pro-Palestinian and pro-terrorist stance marks yet another chapter in the longest hatred of all: anti-Semitism.
Given that Karl Marx accepted in principle the right of Jews in a bourgeois society to demand civil liberties, he was not, in this sense at least, anti-Semitic. Still, these so-called bourgeois privileges were of minor consequence in the greater scheme of things. In a post-capitalist world, Judaism—an antiquated religion of the ego, according to Marx—would become redundant: “Under socialism or communism, there was no need for Jews as Jews to maintain their existence.” Marx’s class-based analysis, insists Wistrich, was a key reason for the German Social Democratic Party (SPD), and later the Russian Social Democratic Party (RSDP), to spurn Zionism.
Because Zionism emerged towards the end of the nineteenth century, the SPD had to make sense of a Jewish national movement without Marx, who had died in 1883. It was Karl Kautsky (1854–1934), the so-called Pope of Marxism, who “came closest to applying the Marxist method of historical materialism in a coherent fashion” to the Zionism project. Kautsky concluded that the Jews were “not a race, a nation, or even a people, but a ‘caste’ with certain quasi-national attributes” that would disappear with the arrival of socialism. This expectation that Jews would lose their “illusionary national characteristics” with the fall of capitalism was disproved by the Soviet Union. Even so, says Wistrich, the line taken by Kautsky runs all the way through to present-day neo-Trotskyist and New Left critiques of Zionism.