...but don't people prefer to choose for themselves what to use as an anthem for change?"

True, of course. My point was that Dixie in itself is perfectly suitable to be used in that way. That doesn't mean that people shouldn't be aware of associations with racism that might get in the way of the song in some circumstances. And no doubt these might indeed get in the way of people feeling able to use the song in that way.

As for songs having Irish Nationalist associations, nothing sectarian about that - in principle you can be a Catholic Unionist or a Protestant Nationalist, though in Northern Ireland itself people like that might tend to keep their heads down. "Partisan" is perhaps the word to use in this context rather than "sectarian".