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.