I can only think of two songs where the issue has come up for me and where I will flatly refuse to join in: "Dublin in the Rare Old Times" and "Hey Zhankoye".

In both cases the problem is that the song is not generally seen as saying anything unacceptable: for "Hey Zhankoye" most people simply have no idea of the historical background and the appalling atrocity the song is celebrating, and for DitROT it seems to be generally considered okay to attack a black immigrant as a menace to Irish womanhood because, well, we just don't criticize Irish songs, do we?

Whereas (in the UK at least) "detachment" works fine for a pro-Confederacy or Jacobite song. The causes they advocate are so thoroughly dead and buried that nobody could be manipulated by a song into supporting them.