They don’t believe in the First Amendment. Keep that in mind.

Liberal activists are stepping up their campaign against Fox News Channel by pressuring advertisers not to patronize the network.

MoveOn.org, the Campaign for America’s Future and liberal blogs like DailyKos.com are asking thousands of supporters to monitor who is advertising on the network, which is owned by Rupert Murdoch’s News Corp.

Once a database is gathered, an organized phone-calling campaign will begin, said Jim Gilliam, vice president of media strategy for Brave New Films, a company that has made anti-Fox videos.

The groups have successfully pressured Democratic presidential candidates not to appear at any debate sponsored by Fox, and are also trying to get Home Depot Inc. to stop advertising there.

At least 5,000 people across the U.S. have signed up to compile logs on who is running commercials on Fox, Gilliam said. The groups want to first concentrate on businesses running local ads, as opposed to national commercials.

“It’s a lot more effective for Sam’s Diner to get calls from 10 people in his town than going to the consumer complaint department of some pharmaceutical company,” Gilliam said.

Enviro-thuggery makes an appearance.

Groups like the Sierra Club have targeted Home Depot because they believe it’s inconsistent for the company to promote environmentally friendly products while advertising on a network that has questioned global warming.

Question their orthodoxy, and they’ll try to shut you down.

MoveOn.org is campaigning against Fox because it says the network characterizes itself as a fair news network when it consistently favors a conservative point of view, said Adam Green, the organization’s spokesman.

“We’re not trying to silence anybody,” Green said. “(Conservative radio talk show host) Rush Limbaugh has a right to be on the air — he admits his point of view. Fox doesn’t.”

Then what’s all the Fairness Doctrine pressure about, eh? Green’s a liar. Whether you’re talking about “campaign finance reform” or the Orwellian Fairness Doctrine or this effort to take Fox down, these leftists just don’t believe that you ought to be free to question them.