Trent, I'm confused here - who was stumped, the caller? Vine (the host?), the journalist, Sayle?
Vine was the host and the caller was a member of the public phoning in after the debate.
So the caller said it was a religion, not a nationality or ethnicity - Vine agreed by saying you can convert to become Jewish and someone was stumped. Sorry, I still don't get it - I'm not following the logic.
I was confused by this too but didn't want to say anything I case I was being dumb.