"Mick, it may be just a matter of time. The Unionist emigration and higher Nationalist birth rate will change the majority."

Mind which religion is in the majority won't necessarily change the voting balance from NO for a United Ireland to a YES. As far as I understand it the Protestant population are much more uniform in their NO stance than the Catholic population is in their YES stance. Hence it is prefectly possible to have a majority Catholic population but still lose a united Ireland referendum - just as it is possible and probably preferable that there could be a swing of opinion and softening of a Unionist stance that there could be a YES vote with the current Protestant majority. Surely the longer they work together and the further away the Troubles become then stances may get more in line. I suspect the Republic itself would much rather have a fair proportion of the Protestants voting for or at least accepting a UI rather than have 49.9% of the Northern Irish brought into a UI kicking and screaming!