It may have been added because communism is a concept that was created by Zionists. Marx was a Jew/Zionist. I don't know if anyone realizes that he also wrote a book addressing the Jewish question. It is very interesting that the leader of communism, who was a Jew, decided to address the Jewish question of the time which resulted in the Balfour Declaration and the eventual pursuit of Israel. How anyone can think that the two things are not related in purpose, is beyond me.Maybe somebody added it to the title, I dunno. Regardless, I'd submit that according to the tenets stated it's been a rip-roaring success.
Communism was very much a part of Zionism and the Jewish question that Zionists like Herzl were also discussing at the time. It was Herzl's idea that Jews should not leave en masse. Communism is basically what the nations are supposed to adopt who are not part of a genealogy or willing to spend the next five generations or so being grafted into this genealogy. You spread communism to the nations, while Israel is created, and in the end there will be only Judaism and communism in theory; or, in other words, there will only be the world and Israel and whatever Israel decides to give the world.
Off topic, but I thought I would elaborate.