A 2009 memo published by progressive think tank and media watchdog Media Matters for America recently surfaced on the Internet, detailing its strategy to discredit conservative media outlet Fox News.

Among the organization's proposed tactics were creating a Fox SWAT team of reporters and researchers to fact-check Fox News stories and publish any inaccuracies, conducting background checks of Fox News on-air personalities and top executives, and gathering video and audio recordings of Fox News employees at conservative events.

We intend to use every tool available to publicly expose News Corp, Fox News Channel and the entire right-wing noise machine for what they really are: a coordinated, corporate-based, 24/7political campaign unprecedented in scale and reach--not a legitimate news source, read the memo, posted on BuzzFeed.

Media Matters has concentrated scrutiny on Fox News and its parent company News Corp. for what it views as the media conglomerate's promotion of a conservative political bias aimed at destroying the Obama administration and its progressive agenda.

Fox News reported on the memo Tuesday in an article posted on its web site's politics page.

Liberal media watchdog group Media Matters once contemplated harassing Fox News employees with yard signs in their neighborhoods, hiring private investigators to dig into their personal lives and retaining a major law firm to study legal action against the network, according to a report Tuesday in the Daily Caller, read the article.

Again, citing the Daily Caller--a news site founded by Fox News contributor Tucker Carlson and Neil Patel, former aide to Vice President Dick Cheney--Fox News implicated Politico reporter and editor-in-chief of BuzzFeed Ben Smith in Media Matters' campaign against it, saying that Smith held a copy of the memo since 2010 and would write stories at the direction of Media Matters. The claims were attributed to an unidentified source said to be a former employee of Media Matters.

Carlson responded to requests by Politico reporter Dylan Byers to verify the source of these claims, telling Byers: The charge is not our charge. The charge is being made by employees at Media Matters, who would know. This is not an editorial, it is reporting that we did out of which came the claim that we wrote in the story. I can't add to what they've already told us.

Byers criticizes Carlson's failure to attribute the claims to an identifiable source, writing: In publishing those quotes without providing evidence, the Daily Caller has put accusations on the public record regardless of whether or not they carry any weight.

It is clear that in Media Matters' war against Fox News, it has an enemy in Carlson and the Daily Caller, and perhaps an ally in Politico.