Another song to commemorate Bloody Sunday Derry, N Ireland 30 Jan 1972 is Séamus Heaney's THE ROAD TO DERRY. The lyrics have been posted on a Heaney Poem thread on Mudcat https://mudcat.org/thread.cfm?threadid=152057. I've found recordings of the poem recited, but not of it sung. Some people do sing it as a song.