Do you have a smartphone? Then you have a recording device.
I had an instructor when I went back to school in 2003 who was an absolute overt socialist. Claimed it outright. Problem was, the classes he taught had nothing to do with politics.
I challenged him at every turn, and he hated it. But because I a) comported myself with professionalism and cheerfulness, and b) studied my ass off and got straight As in every single class, he had no choice but to give me what I went there for: my grades and my degree.
Not only that, but I earned the title of class valedictorian, and being that he was the head of the business department, he was selected to introduce me and my speech. I could tell it grated him to say nice things about me. It grated him even more when I used my speech time to correlate my academic success with personal responsibility.
Be the best you can be friend. That is your best weapon.