When Fox News chief Roger Ailes sent one of his national security correspondents to interview then-General David Petraeus in 2011, chances are he didn't want the full conversation to ever see the light of day -- because if it did, the network's claim of being "fair and balanced" could be forever buried.

As it happened, someone was recording. The Washington Post revealed Monday that Ailes had contributor K.T. Mcfarland deliver a message to Petraeus directly: run for president as a Republican and News Corporation chairman Rupert Murdoch will bankroll you.

Audio of the discussion, published by reporter Bob Woodward, was aired again Tuesday night by MSNBC host Rachel Maddow, who couldn't quite figure out why such a "strange bombshell" of a story would run in the Post's "Style" section instead of near the front of the paper.

"That recording was made April 16th of last year," she explained. "A week and a half later the president announced he was nominating General Petraeus to head the CIA. Right before the president announced him as his choice, the chairman of Fox News was urging the general not to take the job, not to take any job short of being [chairman] of the Joint Chiefs, saying he should run for president instead as a Republican against President Obama in this past election. And it's all on tape."

The moral of this story: Maddow explained that almost more than anything yet revealed, this audio makes it clear that Fox News "seriously is not like anything else in news. They are officially just a media arm of the Republican Party. They are a political operation serving the needs of the Republican Party. That's okay, but we should stop thinking of them as something other than that."

The last person who said something similar on Fox News, Pulitzer-winning military expert Tom Ricks, was immediately taken off the air. He later told The Washington Post that MSNBC is "just like Fox, but not as good at it."

This video was aired by MSNBC on Tuesday, December 5, 2012.

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