Hi Peg!
I have a different take on the song being fun to sing. I have a twin, to whom I am not related, who is so like me, that his sister Liz mistook me for him, so close she has jabbing me in the ribbs, and it took several minutes before she believed that I was not Tony joking with her. Well, Tony and I became close friends, and really like brothers. His brother Patsy O'Hara died on the same hungerstrike as the writer of this song, Bobby Sands. Tony was Bobby's cellmate at the time he wrote the song.
I can't see it as a fun song to sing. It was written while those in Long Kesh concentration camp where held naked in concrete cold cells, in their own filth, as in order to be allowed to clean out the bucket that was their toilet, they would have to put on a prison uniform and acknowelge that the jailing without trial was a legal action.
The words are in no way subtle, when Sands refers to the Irish convicts in their own slime, that, to those of us who intimately know what happened, brings up a host of real horrors which Irish people suffered at the hands of a uncaring colonial power - cavitiy searches used as humiliation and punishment, it would take a book to explain why this is not a fun song to sing, and I shudder when, in Irish American pubs, it is sung causaly with no understanding.
All the best
Larry