I don’t think separating is necessary. It’s messy now, but the amount of posts per day is low enough that the messiness doesn’t cause you to miss ongoing conversations because the section is overflowing. Like damage said, separating too much could simply cause ghost towns.
If organization is the issue, perhaps we could simply add tags to the threads that denote the different topics? So like if I have no interest in the EU, I can just skim over any thread with, say, a purple icon.