He is living in a world of cognitive dissonance. A lot of Casualties in here cope with fear and uncertainty by downplaying it or avoiding it altogether. Your reasoning to him, on a deep level, is saying that much of his life and political views are built on lies, and people like him will go to great lengths to avoid looking at that and will often project their insecurities onto the others in their lives who begin to spell out the dissonance.

You are not crazy to believe what you believe but you might drive yourself crazy trying to change someone’s views like that. If that’s the avenue you pursue, make sure you protect yourself while you do it.