Three strikes, you're out.

Seems like Barack Obama's advisers have a problem keeping their gobs shut. First came Austan Goolsbee, the Dickensian-monikered University of Chicago professor and Obama economic guru who may or may not have told Canadian consular staffers that, in one official's formulation, his boss's fiery NAFTA rhetoric “should be viewed as more about political positioning than a clear articulation of policy plans.” *** Then there's foreign-policy aide Susan Rice, who earlier this week admitted, live on MSNBC, that "they"--meaning Obama and Hillary Clinton--"are both not ready to have that 3:00 a.m. phone call.” Last, but hardly least, is Samantha Power. In an unguarded interview published last night in the Scotsman newspaper, the Harvard professor unleashed a questionable personal attack on Clinton. "She is a monster," Power said. "She is stooping to anything." Did we say questionable? We meant brutal.

Power quickly tried to retract the remark, but with the British press, there's no going back. After spreading last night through the blogosphere and landing atop this morning's "Today" show, the "monster" comment prompted predictable calls from the Clinton camp for Power's head--and Power dutifully succumbed. "I made inexcusable remarks that are at marked variance from my oft-stated admiration for Senator Clinton and from the spirit, tenor, and purpose of the Obama campaign," she said in a statement sent to reporters at 11:44 a.m. "I extend my deepest apologies to Senator Clinton, Senator Obama, and the remarkable team I have worked with over these long 14 months."

As many observers have noted, gaffes like these are a natural result--and risk--of running a "movement campaign." Obama has surrounded himself with bright, energetic political neophytes--many of whom clearly haven’t mastered the art of shutting up. In some ways, the "honesty" of Obama's surrogates is refreshing. But it's also bad politics, and after two slips, he simply couldn't afford to give Power a pass. Nor should he have. While Goolsbee and Rice made fundamentally accurate--if politically inconvenient--remarks about policy, Power simply called Clinton a nasty name.

The incident is less interesting to me as a scandal--I mean, really--than as a symptom of the growing rancor between Obama and Clinton supporters. Some reader comments on Stumper and other blogs are insightful. But most of them have little to do with the post in question. Instead, the exchanges quickly descend into what Internet lexicographers call "flame wars"--malicious, escalating, ad hominem attacks on the rival candidate and anyone dumb, deluded or debased enough even consider voting for him or her. Sociologists, in fact, have a name for this process: "infrahumanization," or, as "GlennWSmith" writes at Open Left, "the tendency for in-group members to strip out-groups of full human emotions and capabilities." In other words, infrahumanization occurs when "we" start seeing "them" as a little less than fully human. A mild, subtle form of dehumanization--which renders others completely non-human--it's not "limited to the close-minded and the bigoted," as Smith notes. Instead, it "seems to be rather universal."

As the campaign drags on and Dems on either side dig in, the infrahumanization is clearly increasing in intensity. Clintonites, for example, like to call Obama supporters "cultish." It's a shorthand way to suggest that they lack reason and emotional stability--making it easier to justify attacks. ("We can reassure ourselves they won't hurt like we'd be hurt because they aren't exactly like us emotionally," writes Smith. "We can and do suspend our empathy.") Of course, infrahumanization occurs every election cycle. But this time around, the Internet--where supporters establish the public tone of debate--is undeniably an aggravating factor. Research has shown that "physical proximity usually mitigates against the infrahumanizing tendency we all seem to share"--and proximity is precisely what the Web prohibits. Couple online anonymity with an endless, evenly matched campaign centered not on policy differences but on personal qualities--including the sensitive issues of race and gender--and you've got a recipe for a whole new level of divisive Dem-on-Dem hostility.

Passion, of course, is fine. Calling someone a "monster"? Sort of counterproductive. It's good that Power has zipped her lips. But the fact is, one prominent adviser can't do nearly as much damage as millions of anonymous, "infrahumanizing" voices. And they only seem to be getting louder.

*** To clarify: Goolsbee denies using those words, but despite recent reports that the original leak referenced the Clinton camp (not Team Obama), it is an incontrovertible fact that Goolsbee met with Canadian consular officials in Chicago and said something that they interpreted as suggesting Obama's NAFTA rhetoric was more extreme than his plans. The unfortunate part is that while a Clinton staffer may have indeed originally told Canadian officials to take HER words with a "grain of salt"--as the initial leaker said--somehow the Canadian press started digging in Obama's sandbox. I don't know how that happened. But in the end, the AP turned up this memo confirming and describing Goolsbee's meeting with the Canadians. So it happened, end of story. Here's the relevant passage:

The memo obtained by the AP was widely distributed within the Canadian government. It is more than 1,300 words and covers many topics that DeMora said were discussed in the Feb. 8 "introductory meeting" between himself, Goolsbee and the consul general in Chicago, Georges Rioux.

Goolsbee "was frank in saying that the primary campaign has been necessarily domestically focused, particularly in the Midwest, and that much of the rhetoric that may be perceived to be protectionist is more reflective of political maneuvering than policy," the memo's introduction said. "On NAFTA, Goolsbee suggested that Obama is less about fundamentally changing the agreement and more in favour of strengthening/clarifying language on labour mobility and environment and trying to establish these as more `core' principles of the agreement."

Goolsbee said that sentence is true and consistent with Obama's position.