In discussions like this, the meaing of words is critically important. Your use of the term "Brtish" is still ambiguous. http://en.wikipedia.org/wiki/British_Isles_%28terminology%29 should give you some insight.
British notionally means someone with a UK passport, which includes the non-foreign residents of Northern Ireland. Surely that is not your intent. Is it possible to parse the Irish from non-Irish in Northern Ireland today. Its like trying to parse New Yorkers from New Jerseyians (sp?). How long does you family have to be there before you get a voice?
The problem is this:
For centuries England dominated Ireland, and persecuted the Irish Catholics. I do believe the Ulster Scotch-Irish, etc. should be equally represented, but England itself should have no say in what is decided.
England needs to stay out of the situation.