Originally Posted by TheVileOne
Red Skull wouldn't have turned on Hitler.
Having Red Skull kill the only Nazis in the movie was weird and made no sense to me.
Red Skull in the MCU is different from the comics version. Johann Schmidt turned on Hitler because he considered the dictator weak and misguided. Schmidt thought himself superior to all of humanity, Hitler included, after he took the serum, and thus he felt that he alone should rule the world. Unlike the comics version, he had powers of his own (physically), so it made sense that he would not want to be Hitler's lackey when he himself was not only stronger, but a genius in his own right. By taking HYDRA under his own command he also developed the military prowess to threaten both the Axis powers and the Allies and potentially defeat all of them. Given all that, the film provided more than enough justification for Schmidt's betrayal of Hitler and the Nazis.