What makes a good statement in a discussion about politics?
I don't find most discussions about politics productive.
People are primed to be defensive about political topics. In the best case, political views are core to a person's worldview and disagreement with those is like saying you want a worse world. There's also an element of group identity - ask someone who identifies as republican about Trump's corruption and they won't defend it head on but will instead counterattack; ask someone who identifies as democrat about benefits fraud and they'll probaby deflect to another topic. Neither of these people would make an argument for corruption or benefits fraud, but they've found themselves arguing for the entirety of someone else's bag. People can't unbundle the bag in a discussion, so the other person interprets the bag holder as either ill-intentioned or uninformed for continuing to hold the bag with the obviously bad thing in it.
We also don't see positive examples of substantial disagreements in our every day lives. On the news, political discussions largely consist of rhetorical maneuvers to position oneself for decisive "mic drop" moments (woe be to the left winger inexplicably employed by fox news who seems to keep losing arguments). And highly upvoted comments on social media are mostly "mic drops" that tear down proposals while offering nothing of substance.
I'm not sure where the good substantial political discussions are. LessWrong and Scott Alexander's writings have some of the better examples I know of. I also recently saw a neat Alan Fisher video about how to understand baby boomers' negative perspectives on city centers, which I found refreshingly two-sided.
I think the key to substantially disagreeing is to not attempt a head-on political debate. Instead when I expect I'll disagree with someone, I try to steer the conversation through talking about us as people first - talking about challenges and what we look forward to, and generally humanizing things. And when we get near a hot topic, if I have a strong opinion, I'll try to indicate that I understand it well, naming the strongest points for and against. For some reason I also try to express some sort of radical amoral understanding - eg "even if a country doesn't really want a nuclear bomb, it can make sense for them to invest in a nuclear program, given that they can trade it for many times its price in negotiations". And after all that, if the person asks me directly or shares their opinion, I'll say my actual opinion on the topic, hoping that I leave a lasting impression without any easy way for them to wave me off as ill-intentioned or uninformed.