Actually, Joel should have thrown the question right back in their face : How about it Whoopie ? Barbarba ? how about those Muslim African countries who are murdering, slaughtering, genocide, hundreds of thousands of innocent Christians ? what about that evil and sin ?
Hindsight is 20/20. I don't think he went on the show with the mindset to debate Christian v. Muslim theology. He seemed pretty taken-aback by the speed and ferociousness of their attack(s).
He made the mistake so many do - he took the liberal media at their word.