On the January 4 edition of Fox News' The O'Reilly Factor, National Public Radio (NPR) senior correspondent and Fox News contributing political analyst Juan Williams said of talk show host David Letterman's treatment of guest Bill O'Reilly during the January 3 edition of CBS' Late Show with David Letterman: “It's like someone inviting you into their house and you find out you've been invited in by, you know, John Wayne Gacy, the clown killer." Referring to Letterman's interview of O'Reilly, which Williams further labeled a “knife fight,” Williams said, “I'm surprised you don't have a black eye this morning.”

"[T]he culture war plays out on the David Letterman program," O'Reilly said of his appearance on Letterman's show. O'Reilly went on to state that two main issues dominate this culture war: “the role of God in the public arena and the war on terror, including the Iraq campaign.” O'Reilly then characterized the culture war over Iraq as a split between the “secular progressive movement” which “sees America as the wrongdoer in the conflict” and "[t]raditionalists" who “see the USA as doing something noble.”

Later on the show, Williams agreed: “I think there is a culture war in the country.”

From the January 4 edition of Fox News' The O'Reilly Factor:

O'REILLY: But first, the “Talking Points Memo”: The culture war plays out on the David Letterman program. Right now, there are two main issues dominating the culture war in America: the role of God in the public arena and the war on terror, including the Iraq campaign.

The Christmas controversy was all about the ACLU [American Civil Liberties Union] and others trying to de-emphasize Judeo-Christian tradition in America. All the nonsense was because of that.

On the Iraq front, the secular progressive movement sees America as the wrongdoer in the conflict. Traditionalists see the USA as doing something noble.

[...]

WILLIAMS: I think there is a culture war in the country. I must say I was surprised, given his antagonism towards you, that he had you on the show. In some sense, it's like someone inviting you into their house and you find out you've been invited in by, you know, John Wayne Gacy, the clown killer. Because here he is saying, “Oh, I'm just throwing spitballs.” Spitballs? He said he doesn't believe 60 percent of what you say, Bill. This was a knife fight, and I do believe it was over culture. When you think about him saying some of the, I think, horrible things that he said to you, I'm surprised you don't have a black eye this morning.