Attack the idea that America is a democracy. If America isn't a democracy, it can't be reformed through democratic means.
Start with the obvious things, like the electoral college, misapportioning of senators(1 voter in Wyoming has the same representation in Senate as 59 people in California), the two party system. The power of money, lobbying, etc. Talk about the ideas that have long had broad support, but aren't being dealt with, taxing the rich and big corporations, like modest gun reforms, dealing with political corruption, codifying roe v wade, etc.
Edit: You won't get there in one discussion, but you can plant the seed.