Regional chauvinism is never good for a healthy union. Even if it were the Union Jack, flag-shaggers are almost always blood and soil zealots.

I think a small level of it is fine. It’s like sports teams. You can be a Giants fan and I can be a Yankees fan, and we’ll bicker & make fun of each other for supporting a different team. But we can still work together & be civil when it comes to lots of other stuff.