One awkward, unscripted moment after a silky-smooth speech and the mystique Mahmoud Ahmadinejad spent more than a half hour crafting for hundreds of scholars and students Monday at Columbia University evaporated into pitiful ether.

Who can take the president of Iran seriously when he looks squarely at an audience at one of the leading universities in the world and insists there are no homosexuals in his country?

"In Iran, we do not have this...