How to show my friend the error of his way?

My friend started reading nazi books from the school library and although I've fallen into an apreciation for the nazis once I quickly saw my error but my friend has gone to deep into nazism he draws swatsikas on his palms and once said he ran into a jewish guy at the gas station and said he wanted to strangle him... I don't want to be a hipocrite by saying that they are evil and wrong since I've appreciated them once but. He's my best friend he's always talking about the third reich and has a nazi swatsika on his binder and has a picture of an mp-40 on it too reading " we lost the war..but we will return!" My friends and I are annoyed about how often he talks about hitler and the third reich.. the weird thing is that he wants me to support him and even though I'm his friend I try to be his support even though I hate the nazi ideals... he even told me to drive him to the public library to see if they had "mein kampf" written by adolf hitler....I'm just worried because both of us are joining the united states army when we grow up and I'm afraid his ideals are going to prevent him from joining... please help me show him the error of his ways