My father-in-law and I used to get into long political debates about Bernie Sanders, who he hated with a passion, and socialism. He grew up in Russia and luckily escaped before the fall of the USSR. No matter how much I tried to sway him towards my position, he would always remind me that his politicians promised the same thing to him when he was younger. And it turned to shit. He would NOT fall for that trap again. 

I think @dwr.eth’s comment is a good reminder of the personal world view that individuals bring to political conversations. Of course, he’ll never be convinced. His family experienced communism in the worst form. Why would they agree to try it out again?

Very much in the same way that many of us, myself included, can’t be convinced that capitalism unchecked is good. Because we have lived through it. 

The point of political discourse shouldn’t be to convince others to come to your side but to reflect and take in others viewpoints so we can move forward good policy together.