As FReeper Beautiful_Gracious_Skies said, “If it walks like a duck...” When you need Harry Belafonte, who has never yet found a Communist dictator he doesn’t praise, to handle and manage you for a tv talk show, you cannot possibly be signaling where you stand any louder. The more you dig into MLK’s life, the uglier it gets. A photo op with Nixon won’t change that.
We’re going in circles with this discussion.
Maybe, but then again, why write an essay condemning Communism as antithetical to Christianity if he was one, and explicitly state they will never reconcile their differences, if he was a Communist? Even under Taqqiya-type lying, that has absolutely no tactical or strategic value for the Communists, especially when making very clear that fundamental truth that Communists and Christianity simply cannot mix together would destroy any potential propaganda value of converting Christians into Communists. In fact, if I were Harry Belafonte, a Communist ideologue in other words, and I saw MLK wrote that, I’d scream at him as being a traitor to the revolution and shoot him dead for publishing that paper.
Besides, going by the argument “if it walks like a duck...”, you could also argue that Abraham Lincoln is a closet Marxist for doing correspondence with Karl Marx, not to mention Horace Greeley being one of his key members of the Republican Party (and Greeley is obviously a Karl Marx fanboy based on his hiring him and Engels for correspondence and advocating for many of the same radical reforms). Hope you’re prepared for that possibility.