And also the United States form a federal republic. It makes sense for the states qua states to have a voice in the federal government (just like it makes sense

And also the United States form a federal republic. It makes sense for the states qua states to have a voice in the federal government (just like it makes sense for the states of Europe to have a voice in the European Union government). If anything, I would push the principle downwards further, and argue that state senators should represent counties. Indeed, this was the case until the execrably unconstitutional Reynolds v. Sims decision in 1964, which forced states to apportion state senate seats by population. We would probably be a much happier union if our politics were mostly about those things most of us can agree on, rather that all about the things that we disagree on. Our politics is all scissor statements, now.