I'd quite like that guy to have explained why he brought up the Barbary slave trade, which doesn't seem to have anything to do with the Elgin marbles at all.
Also -- while it may or may not apply to this particular interviewer, I don't know -- it's a common interviewing strategy to be adversarial, whether you agree with the line of questioning or not. The point being to allow the interviewee to respond to challenges and expand on their point, or to perhaps expose a flaw in their position that can later be addressed. This guy didn't do that, at all, and seems to be more keen on looking smug and firing put-downs.
To "destroy" the interviewer would have been to advance a coherent argument that deflected all lines of questioning and made the argument look stronger as it went on. We never even got this guy's argument. "Do you know about the Barbary slave trade? No? Then eff off" isn't destructive.
i think the guy was obnoxious and quite rude. there is nothing anti british about the question either so once again ttt describes anyone who disagrees with him as being a traitor
what happens here is that the interviewee asks for the question to be explained
the interviewer says that the elgin marbles were taken from greece during a war with the ottoman empire
the man then interrupts rather rudely and asks whether they were this involved people who "took our people as slaves" (it didn't) and tells the interviewer he's not worthy to ask the question
I'm not saying that there's no link at all. But my point is that we never got to hear it -- or, at least, this person's understanding of it. For example, the Elgin marbles are (Ancient) Greek, and came from the Parthenon, etc; while they were moved to Great Britain under Ottoman rule, that alone can hardly be enough to make a link to the Barbary slaves.
// Perhaps he just objected to his country being trashed to foreign viewers. //
Perhaps, but then again perhaps he had an opportunity to put the case for keeping the Marbles in the UK. I mean, surely there is one; and surely this isn't something that he gets asked about personally often enough to be irritated by the question.
the question of whether they should be returned is perfectly valid. if he objects to people even asking the question in public then he should be less of a baby and put on his big boy pants