Dagobert D. Runes writes,
Karl Marx was not only born a Jew; he came from a rabbinical family. His father Heschel Marx accepted Christianity in 1816 in order to practice law in Prussian territory. Like many converts, Marx found it necessary all his life to justify the mass conversion of his family by attacks against his blood brothers.
Runes wrote this in the forward to a A World Without Jews, a book attributed to Karl Marx, published in 1959. But Karl Marx never wrote a book called A World Without Jews. Moreover, the essays that form the chapters of this book are collected from essays published separately, and include passages that do not appear in previously published versions.
Focusing on the above quoted passage, there are two problems with it. The first is the wrong of classic psychological ad hominem. To suppose Marx was psychologically motivated to criticize Judaism and the role of Jews in European society, whatever the reason, is a fallacious argument form. Marx’s argument in the essay is well constructed and, assuming someone with the same intellect, a criticism a man or woman of any ethnic background could make.
The second problem is this phrase “blood brothers,” as in Jews are blood brothers and therefore a Jew who criticizes Judaism is a race traitor. Runes is here embracing the racialization of Jews, an imposition upon Jews by non-Jewish Europeans who sought to make them something other than Europeans. This is the wellspring of anti-Semitism. Jews are Jews by blood. Jewish blood must be something different than non-Jewish blood. This means that creating a Jewish state in Palestine is the creation of a racial state.
The bulk of the argument Marx is making is found in the 1844 essay “On The Jewish Question” in Deutsch-Französische Jahrbücher. It which was a response to Bruno Bauer’s 1943 book Die Judenfrage (The Jewish Question). Bauer’s book is complex, and I may return to a discussion of it on a later date, but the substance of Marx’s argument written in the context of his critique of Bauer is that liberation from religion would mean liberation from Jews, Christians, Muslims, etc. Marx was an atheist who advocated overthrowing the world order—capitalism—that underpinned modern religious ritual. A world without religion and capitalism would be a world without Jews because Judaism is a religion. The same would be true for Christians and Muslims. And so on. In other words, the argument is not anti-Semitic but rather anti-capitalist and irreligious. Indeed, Marx argued on behalf of Jewish liberation in Germany.