Russert said he knew Cheney lied about not meeting Edwards -- so why didn't he mention it in his post-debate commentary?

Following the October 5 vice presidential debate, NBC's Meet the Press host Tim Russert repeated without challenge Vice President Dick Cheney's claim that Cheney had never met Senator John Edwards until the debate, but Russert knew Cheney's claim was false: Cheney and Edwards appeared on the same 2001 broadcast of Meet the Press. Russert said on the October 6 edition of NBC's Today show: “I thought that John Edwards would call him [Cheney] on it right at that very moment.”

Here's what Russert said during an October 5 post-debate appearance on MSNBC:

RUSSERT: [W]hen he [Cheney] turned to John Edwards and basically said to him, you know what, you are a young man in too much of a hurry. I never met you before in my life until you walked on the stage tonight, it was basically saying to the American people, you may disagree with me, but I am steady and I am resolute, and I have a lot of experience, and you don't have to worry about the government if I am a heartbeat away.

And here's what Russert said on the October 6 edition of NBC's Today show:

KATIE COURIC (Today co-host): [I]t was interesting how they didn't really respond to each other's criticisms. Oftentimes they would -- somebody would make a point, and then they wouldn't be responsive, they would just say another point against that candidate. For example, the vice president said he had never met John Edwards until tonight, talking about pretty much being an absentee senator, but you say that's not true.

RUSSERT: No, it's not true. In fact, on April 8th of 2001, they were on Meet the Press together. Dick Cheney first, and then John Edwards after him.

COURIC: Well, why did he say that?

RUSSERT: And they stopped and shook hands. They were at a prayer meeting together. I think what he was trying to -- maybe he didn't remember -- but he clearly is trying to give the impression that John Edwards is a young ambitious man in a hurry who just doesn't stop by the Senate and do his job in a serious way, but is out campaigning and politicking, suggesting it's all politics. I was surprised that --

COURIC: On the other hand, if you -- if you misspeak like that and -- and are dishonest about it, that can backfire, right?

RUSSERT: Sure. I wish -- I thought that John Edwards would call him on it right at that very moment. I still don't know why. I think it goes to your point, he was always trying to find a -- a bigger issue to take on.