Explores the transformation in attitudes on the Left toward the Jews, Zionism, and Israel since the origins of European socialism in the 1840s until the present. Reveals a striking continuity in negative stereotypes of Jews, contempt for Judaism, and negation of Jewish national self-determination from the days of Karl Marx to the current left-wing intellectual assault on Israel. Provides not only a powerful analysis of how and why the Left emerged as a spearhead of anti-Israel sentiment but also new insights into the wider involvement of Jews in radical movements.