Anti-Semitism is dangerous for the toilers, for it is a false track which diverts them from the proper road and leads them into the jungle. Hence, Communists, as consistent internationalists, cannot but be irreconcilable and bitter enemies of anti-Semitism. In the U.S.S.R., anti-Semitism is strictly prosecuted as a phenomenon hostile to the Soviet system. According to the laws of the U.S.S.R. active anti-Semites are punished with death.
"Anti-Semitism: Reply to an inquiry of the Jewish News Agency in the United States" (12 January 1931)