The new contestant in the 7,000th Democratic debate, which took place in Las Vegas on Wednesday night, was former New York City Mayor Mike Bloomberg, who got on the debate stage by spending 400 million dollars, and most of the key discussion focused on his candidacy and his record.

Practically the whole field united to savage Bloomberg. Joe Biden, Elizabeth Warren, Amy Klobuchar, and Bernie Sanders all attacked him more aggressively than any candidate has attacked another at any previous debate, and Bloomberg was all but helpless before the withering assault. Though he has bought off dozens of Democratic politicians and think tanks, it seems like all but one of his competitors are not at all keen on their party being bought wholesale by a billionaire oligarch.

The most riveting moment of any Democratic debate so far came almost immediately, when Warren nailed Bloomberg on his appalling record of sexual harassment, racism, and plutocratic corruption:

I'd like to talk about who we're running against — a billionaire who calls women 'fat broads' and 'horse-faced lesbians.' And no, I'm not talking about Donald Trump, I'm talking about Mayor Bloomberg. Democrats are not going to win if we have a nominee who has a history of hiding his tax returns, of harassing women, and of supporting racist policies like redlining and stop-and-frisk … Democrats take a huge risk if we just substitute one arrogant billionaire for another. [Elizabeth Warren]

Later, when Bloomberg tried to deflect a question about allegations of workplace harassment, Warren pounced again: "He has gotten some number of women — dozens, who knows? — to sign non-disclosure agreements both for sexual harassment and for gender discrimination in the workplace. So Mr. Mayor, are you willing to release all those women from those non-disclosure agreements, so we can hear their side of the story?" (By the way, the total number is at least 64 women as part of 40 different lawsuits.)

Bloomberg again tried to deflect, arguing that the agreements were made to protect the privacy of the women involved. "They decided when they made an agreement that they wanted to keep it quiet." Biden then joined in, pointing out the obvious fact that this is not what NDA agreements are really about. People take the money, and in return they agree not to discuss the horrible event. It's basically hush money, and the American people deserve to know the truth. "All the mayor has to do," Biden said, is tell those people, "'You are released from the nondisclosure agreement.'"

Bloomberg still did not agree to release the agreements, but he was completely nonplussed by the exchange. He clearly was not prepared for these rather obvious questions, perhaps because he is a cloistered plutocrat surrounded by yes men and toadies, or perhaps because there is no defense at all. He appeared very much like what he in fact is — a very rich man who is likely facing bitter, unfiltered criticism to his face for the first time in years.

The only candidate who largely refused to leap on the dogpile was Pete Buttigieg. When Biden and Warren were mercilessly destroying Bloomberg on his sexual harassment history, Buttigieg did not join in. When Klobuchar was attacking Bloomberg for failing to release his tax returns (as Trump has also refused to do), Buttigieg stood aside. When Sanders was attacking Bloomberg for endorsing George W. Bush in 2004, and for being a gigantic vector of corruption in the political system, Buttigieg said nothing.

In his one clear attack on Bloomberg, Buttigieg triangulated himself between Bloomberg and Sanders. "Most Americans don’t see where they fit if they’ve got to choose between a socialist who thinks capitalism is the root of all evil and a billionaire who thinks money ought to be the root of all power," he said. "We shouldn’t have to choose between one candidate who wants to burn this party down and another candidate who wants to buy this party out."

Every other candidate, especially Warren, seemed genuinely infuriated at the prospect of a racist, sexist, authoritarian former Republican like Bloomberg buying the Democratic nomination like a slurpee at 7/11. But Buttigieg, well, he's cut from a different kind of cloth.

It remains to be seen how much Bloomberg's epic debate faceplant will matter when it comes time to vote in upcoming states. He is spending a totally unprecedented amount of money on this primary. But this was by far the most interesting and dramatic debate of the primary season, and he ate it big time. It doesn't speak well for his ability to hold up under the scrutiny of a general election campaign, where his money will be a lot less useful than it is right now.

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