The Center for American Progress is celebrating its 10th anniversary today with a policy conference and a “progressive party.” Not exactly coincidentally, this column is also 10 years old—10 years and a day, to be exact. My introductory column was called “Think Again: Who’s Driving This Train?” and appeared on this website on October 23, 2003.

By a rough estimate, this is my 500th column; what a long, strange trip it’s been. American politics has grown more extreme and unwieldy during the past decade, owing largely to the simultaneous radicalization and flight from reality of the conservative movement and its takeover of the Republican Party. What was so remarkable about the recent government shutdown and near-default was, as conservative columnist Ross Douthat pointed out in a column called “The Kurtz Republicans,” that “Even the shutdown’s ardent champions never advanced a remotely compelling story for how it would deliver its objectives.” As pundit Paul Rosenberg recently wrote for Al Jazeera English, the media ignored nine bodies of evidence that clearly showed it was Republicans, not Democrats, who caused the shutdown.

The mainstream media’s greatest failure has been its members’ inability to acknowledge this reality. Over and over, no matter what the issue—no matter how outlandish, illogical, or simply untrue the conservative argument has been—journalists create a sense of false equivalence between positions that rest on data and logic and those that don’t. To quote Cenk Uygur, “If CNN did sports reporting, every game would be a tie.”

The clearest example can be found in the global warming debate where, as I recently argued, “The mainstream media irresponsibly treats uncredentialed climate deniers … with the same degree of respect as climate scientists who are qualified” to judge the problem. In doing so, they ignore the fact that, led by massive investments from Charles and David Koch, “Conservative billionaires used a secretive funding route to channel nearly $120m (£77m) to more than 100 groups casting doubt about the science behind climate change.”

Oddly enough, my first column also focused on the problem of false equivalence. Here is its opening; the subject was Democrats refusing to support a particularly problematic Bush administration bill to further fund the Iraq War:

Go down the Iraq laundry list; no WMD’s found, bogus intelligence claims, American GIs dying at the clip of at least one-a-day, a billion a week just for security, while Saddam Hussein and Osama bin Laden still roam the landscape. So what’d the press do last week when covering the war? Blame the Democrats, of course. We don’t want to give anyone the wrong impression right off the bat here. This column will not be in the business of flacking for the Democrats, with whom we have many problems and differences, as will become evident in weeks ahead. What we hope to identify here is a dreaded media malady we seek to christen “Ontheonehandism.” This is how the So-Called Liberal Media (SCLM) demonstrates their alleged even-handedness by finding ways to criticize Democrats and liberals even when they’re right, no matter how trivial or wrong-headed the critique.

I also noted that Time’s Joe Klein, NBC’s Chris Matthews, The New York Times’ David Brooks, and Brit Hume and Tony Snow on Fox News—together with the editorial boards of The Washington Post, The New York Times, and The New Republic—all heaped scorn on the Democrats for taking the position of a “solid majority of Americans.” Among the adjectives employed by the critics above were “an embarrassment,” “not plausible,” “illogical,” “shameful,” and likely to make Saddam Hussein “jubilant.”

This was not exactly false equivalence, but it was a precursor of things to come. Even for an issue with a cause as obvious as that of the government shutdown, mainstream reporters cannot bring themselves to assign responsibility where it undeniably belongs. Media Matters for America has helpfully provided us with a compendium of such instances, and here is a similar review from the Nieman Journalism Lab at Harvard University.

The reasons for this phenomenon are complex and interrelated. They derive from mainstream reporters’ outdated commitment to the ideal of objectivity. Conservatives successfully exploit this commitment with their willingness to invent facts, subvert scientific study, and replace reality with ideology. “Both sides” may “do it,” but not to degrees that are remotely comparable.

For a final example, I ask you to compare two institutions and their work over the past 10 years: the Center for American Progress and the Heritage Foundation. Both organizations provide research and analysis to support their political worldviews and are frequently—and foolishly—equated in the mainstream media. But CAP’s research is dependable, academically rigorous, and provided by respected and admired experts in their fields. In the 10 years I’ve been writing here, I’ve not seen a single study whose integrity has been called into question on either methodological or ideological grounds. On the other hand, the Heritage Foundation’s recent reports on health care and immigration—just to pick two fresh examples—have been roundly mocked as factually dishonest and analytically ridiculous. There is no equivalence there, nor has there been for the past 10 years, thank goodness.

Eric Alterman is a Senior Fellow at the Center for American Progress and a CUNY distinguished professor of English and journalism at Brooklyn College. He is also “The Liberal Media” columnist for The Nation. His most recent book is The Cause: The Fight for American Liberalism from Franklin Roosevelt to Barack Obama, recently released in paperback.