If, like PeteBoom, you rule out songs on those kinds of grounds, all the Irish rebel songs would be "invalid": as the desired result, a United Ireland, has still to happen: as it assuredly, eventually, will: by constitutional consent.                                          

So, no "Boolavogue", no "Kelly", no "Minstrel Boy", no "Mullaghbawn", etc: not worth listening to: forget them, futile.

The main thing surely is that some of these songs are truly great: in their own right, irrespective of history.

They exist independently as works of art (as do some of the unionist songs).