Television comedian Jon Stewart, a fierce critic of the conservative bias that he sees regularly on Fox News, has in the past gone on that network's airwaves to defend that opinion, usually on The O'Reilly Factor.

But for the first time ever, the progressive icon appeared on Fox News Sunday with Chris Wallace, where, unlike his forays with Bill O'Reilly, the exchanges on both sides got pretty serious, as you can see from this clip:

Stewart took exception when Wallace said that the Daily Show was making a comment when they compared a video of Sarah Palin's bus tour with a herpes ad.

https://youtube.com/watch?v=RwyUdBp-cck