Well of course the KKK was an aberration. But back in the 20s it was a pretty popular aberration in some places, and not just the South.

What I'm meaning really to get at is that there's no justification for people elsewhere thinking that Northern Ireland is wildly different from where they are. The lines get drawn in different places with different excuses. "Race" is one way to do it, religion is another, and we are quite capable of thinking up new ones. In India it can be caste, in Ruanda it came down to height. Sometimes it's how people dress, or how they wear their hair.

There are always reasons that can set one lot of people against another, and they seem silly reasons to people, who aren't caught up in it, and it's easy to think that where we are is so much wiser and less bigoted. And we forget so quickly – "many generations".

If Prince Charles became a Catholic? The constitutional pundits would freak. It's not just a question of British Law, which currently outlaws a Catholic becoming King - there are all those other countries that theoretically share the same Head of State, so they are knotted into it as well. And his mum definitely wouldn't like it.

But I doubt very much indeed if most people in England would give a monkey's toss. There'd probably be some people saying, let's use this as a chance to drop the Monarchy, but that's be more to do with disliking the Monarchy than with having hang-ups about a Catholic Monarch. (After all, the leader of the Labour Party is virtually a Catholic, the leader of the Liberal Party is a Catholic, and so is the woman whom I'd put my money on to be the next leader of the Tory Party.)

But if it turned out that the Unionists in Northern Ireland refused to remain in the Union with a Catholic King, I think support for having a Republic in the rest of the UK would rapidly diminish. Having a Catholic King would be seen as a small price to pay for that, even among people who don't like Catholics.