This type of discussion is interesting. I'd always thought of nationality as being (objectively) determined by the birthplace/nationality of your parents, but obviously it depends on your upbringing too, and how you choose to define yourself. In terms of his parental heritage Morrissey is Irish, but the fact that he was born and entirely brought up in England makes him Anglo-Irish in my opinion, and from what he's said/sung about it I should think that's closest to how he would define himself ('Irish Blood, English Heart' etc).