I can think of three (inadvertent) positives that came out of Lou Dobbs' ill-advised embrace of the birther movement: the CNN host has permanently tarnished his reputation; the birther movement is officially kaput; and Rush Limbaugh is afraid to talk about birthers.

I can think of three (inadvertent) positives that came out of Lou Dobbs' ill-advised embrace of the birther movement:

1) The CNN host has permanently tarnished his reputation

2) The birther movement is officially kaput (like, stick-a-fork-in-it done)

3) Rush Limbaugh is afraid to talk about birthers.

Talk about a win-win-win.

It's true that Dobbs irresponsibly mainstreamed radical right-fringe players by championing their half-baked claims that Barack Obama isn't a natural born citizen and is ineligible to serve as president of the United States. Dobbs, at least indirectly, lent the birther movement some fleeting credence as he dragged its misbegotten detective work into the spotlight. And it's still vitally important to monitor Dobbs and call out CNN management for its dreadful hypocrisy on the birther issue (i.e. The story is “dead” but it's OK for Dobbs to keep flogging it on national TV).

But there was some good news last week, and it came from watching Dobbs' slow motion train wreck unfold on the airwaves. It came from seeing how eagerly -- how convincingly -- the birther claims were debunked, not only online by progressives, but within the mainstream press as well -- the same mainstream press that's often reluctant to show up high-profile media players such as Dobbs, no matter how badly it has botched the facts. And let's not forget conservatives, who dismissed and ridiculed the birther claims.

In the case of the birthers, though, Dobbs' corporate media colleagues were utterly relentless in their fact-checking. I still don't think Dobbs knows what hit him. And frankly, I'm not sure I've ever seen such a well-deserved media pile-on. It's hard to see how Dobbs' career survives the humiliation.

Of course, it's always dangerous when hateful and cuckoo conspiracy theories are ushered into the mainstream and right-wing critics are given a platform to peddle their hateful whodunits about Obama's nationality the way Dobbs did. But, in this case, I almost think it was worth running that risk in order to watch the tidal wave of media disapproval that Dobbs' fearmongering unleashed.

Because in retrospect, the birthers, who had spent months lurking on the sidelines, needed to be called out on national TV; they needed to be ridiculed mercilessly and have their cheerleaders thoroughly mocked. They needed to be turned into the butt of a joke, and thanks to Lou Dobbs, last week they were.

It was a good thing MSNBC viewers got to see right-wing radio host G. Gordon Liddy feebly attempt to make sense of the birther crusade. And let's face it, if it weren't for Dobbs' high-profile, albeit irresponsible, birther cheerleading last week, Chris Matthews never would have booked Liddy for the show, nor would he have been discussing the topic.

Indeed, the rhetorical media beat down that Dobbs suffered seemed to reach every conceivable media forum, with reporters and pundits, anchors and TV hosts all lining up to smack the birther piñata Dobbs had so proudly hung.

Watch again as Jon Stewart pummels the piñata and scoops up the treats:

Watching clips like that convinced me that Dobbs last week inadvertently, yet effectively, buried the birther movement as we know it. Despite its extraordinary resiliency (didn't the Obama campaign first try to debunk this story exactly 12 months ago?), I think by shining a spotlight on the birther conspiracy, Dobbs, rather than helping get questions answered, and rather than legitimizing the lost souls peddling the birther certificate nonsense, helped drive a stake through its heart. The media backlash that Dobbs set off made sure of that, and it made sure that nobody will ever take the birthers seriously again.

Think about it, without Dobbs suddenly out front leading the stragglers who make the birther parade, do you think NBC would have devoted four minutes of its Nightly News to thoroughly debunk the story? I doubt it. And that's why I think everyone now owes Dobbs a hearty round of applause. Because let's face it, he did in one week what nobody else had been able to do during the previous 51: put an end to the birther movement.

And while we're patting Dobbs on the back, I'm pretty sure Dobbs scared Limbaugh off the birther story -- or, more precisely, the pummeling Dobbs received scared Limbaugh off the birther story. And that's a big deal within the Republican Noise Machine. Birthers had been courting Limbaugh for months and cheered in June when the turbo talker at least made a birther joke on the air: “Barack Obama has one thing in common with God. Do you know what it is? God does not have a birth certificate either.”

As David Weigel at The Washington Independent reported:

On June 16, after Limbaugh joked about the president's citizenship, WorldNetDaily editor-in-chief Joseph Farah appeared on the Web-based Recharge Radio to thank the host for spreading the “birther” message. “What that did is beyond Rush's impact,” said Farah. “It also gives other talk show hosts license to talk about this issue ... Rush is kind of the standard of talk show hosts. A lot of people emulate what he does. He crossed the Rubicon on that show, and I'm very proud of him for doing it.”

Earlier this month, just as the Dobbs circus was setting up shop, Limbaugh returned to the topic in a far more serious vein, saying: “Barack Obama has yet to have to prove he's a citizen. All he'd have to do is show a birth certificate.”

That was July 20, around the same time Dobbs waded into the birther pool and just days before the CNN host ignited massive media blowback. But here's the tell: Have you noticed Limbaugh's deafening silence about the birthers since July 20th? Have you noticed how the birther movement was in the news virtually every day last week, how the mainstream press was debunking it and calling out the right-wing nonsense, how NBC's Nightly News referred to Limbaugh in its birther report, yet Limbaugh remained mum? Rather than step forward in his natural role as a birther defender and attacker of all-things Obama, Limbaugh has sat out the birther controversy and watched its members get mowed down in the press.

Limbaugh's scared to talk about the birthers and won't defend them because he has seen how Dobbs and the movement got manhandled by the press -- including by conservative commentators. In fact, Limbaugh himself took some friendly fire from Philip Klein at the far-right American Spectator who, under the headline, “Shame on Rush,” announced: “To any sane human being, there is no controversy.”

Limbaugh saw how the press was sticking to the birth certificate facts and wasn't shy about knocking down high-paid radio hosts who tried to traffic in that nonsense.

And guess what? If Limbaugh won't back the birthers, that means most right-wing AM hosts won't either. Because that business is built upon a very simple (lemming) rule: Do whatever Rush does. And if Limbaugh won't line up on the side of the birthers, than means most AM talkers won't either, which means the birthers are going to be pushed back to the fringes where they belong.

And for that, we have Lou Dobbs to thank.