Nobody is arguing against Communism being a complete worldview. It is but you cannot claim to be a form of atheism. Atheism by itself is nothing but a lack of belief in gods or God. Any number of worldviews may incorporate it. My own particular worldview has little in common with your's outside of atheism. Neither of us may claim atheism as if it belongs to us. Any idiot may claim the universe was created by the lizard spawn of Tom Paris and Catherine Janeway but those fools may not claim kinship with us.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
Albert Einstein
Albert Einstein