This is definately about the troubles facing Ireland.
"Please" is Bono's desperate cry for peace.. I was chatting on-line with another U2 fan, and they drew for me one of the most interesting parallels. In Sunday Bloody Sunday Bono proclaims "I won't heed the battle call", and in Please he proclaims "Please, leave me out of this please". The approach taken in Sunday Bloody Sunday seems to be a bit more confident. I think in Please you can see Bono become more desperate.
"shards of glass, splinters like rain, but you can only feel your own pain"
This paints a picture of exploding bombs, and how selfish it is of the bombers.