We have already reached the point in this presidential contest when the prospect of being hanged is concentrating the minds of the candidates wonderfully.

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We may be almost a full year away from the Democratic convention in Milwaukee, but the grim reaper that stalks the land of TV debates is ready to claim the souls of several campaigns.

Faced with the prospect of losing a precious podium on stage in the next round of debates, the Democrats emerged on the second night of knockabout TV even more pumped for a punch-up than the scrappy crowd who showed up on the first night.

Joe Biden supposedly needed to stand up for himself after taking a few punches from Kamala Harris in their first debate last month. “Go easy on me, kid,” he told her as they shook hands on stage.

These are the sucker-punch tricks of an old streetfighter who spent the last few weeks in the gym. Biden had no intention of going easy on anyone and – to hell with the details – he was going to take down everyone on stage if he needed to.

Did the Harris plan cost $300tn or $30tn? It didn’t matter because she was going to tax everyone, deny them their beloved employers’ insurance, and take a decade to deliver anything.

Harris stumbled over her lines and the fight was on.

The onstage brawl quickly devolved into a confusing combination of sparring partners. Harris said Biden’s plan left out 10 million Americans; Bill de Blasio said he didn’t understand either of them; and Kirsten Gillibrand talked about her baby’s allergic reaction to eggs.

At this point, both Harris and Biden hid behind the magic word “Obamacare” and hoped for the best.

But the otherwise anonymous candidates saw their moment of glory. Even that polite Michael Bennet, a Colorado senator who previously worked as a school superintendent, decided to drop the nice-guy routine to accuse Harris of dishonesty.

“We cannot keep with the Republican talking points on this,” Harris complained. “You’ve got to stop.”

Nobody was in the mood for stopping, least of all Joe Biden. The former vice-president could have declared victory and flashed his blinding smile through the next 90 minutes. But there’s a reason why all his previous presidential campaigns have imploded – and that reason is Joe Biden.

Biden’s debate strategy amounted to attack as the best form of defense, and it didn’t much matter who was on the receiving end. Or whether they had even taken a swing at him. So when Julián Castro talked about his immigration reform plan – the most detailed immigration proposal in the entire field – Biden swung blindly at the former mayor of San Antonio.

When pressed on Obama’s record on mass deportations, Biden said Castro hadn’t complained about it at the time.

“It looks like one of us has learned the lessons of the past, and the other hasn’t,” Castro told the former vice-president, who suddenly seemed to age at warp speed.

And so the desperate brawlers turned on Biden.

Biden’s strategy amounted to attack as the best form of defense, and it didn’t much matter who was on the receiving end

De Blasio pressed Biden on deportations like the last New Yorker pressing his way into an overheated subway car. Did Biden tell Obama to stop the deportations? Biden suddenly grew shy about his conversations with Obama, mumbling something about confidentiality.

“Mr Vice-President, you can’t have it both ways,” said Cory Booker, the New Jersey senator who began the night urging Democrats not to tear each other apart. “You invoke President Obama more than anybody in this campaign. You can’t do it when it’s convenient and then dodge it when it’s not.”

It was all going so well for Biden. Until it wasn’t.

After a lifetime of bragging about being tough on crime, Biden found it astonishingly hard to run towards the new center of Democratic politics. He claimed that his crime bills were passed with overwhelming bipartisan support, but that didn’t exactly end the discussion.

So he lashed out at Booker, and missed. It really didn’t help when he called Booker the president. Or when he called him the future president. Then again, if you talked about President Obama as much as Joe Biden, you too might start seeing him everywhere.

Strangely, Biden then decided to go after President Booker’s record as mayor of Newark, claiming that “nothing happened the entire time you were mayor” in terms of reforming the city’s toxic police force.

Booker locked his eyes on Biden and smiled. “There’s a saying in my community: you’re dipping into the Kool-Aid and you don’t even know the flavor,” he said. “You need to come to Newark and see the reforms we put in place.”

Biden’s record is long, and his party has moved on from the politics that elevated him in the first place. He said Obama’s team of lawyers vetted him and still picked him as vice-president, but there’s no vetting for the politics of the future and there’s no Obama to protect him now.

This Democratic debate was not for the faint-hearted, and its producers made sure of that. There was the WWF-style intro to the warring candidates. There were the military veterans presenting the colors. And there was the national anthem, sung live, as on all great sporting occasions.

Yes, we get it, CNN. You think this is all a great gladiatorial game. After all the hand-wringing about the media’s role in the rise of Trump, the greatest TV producers of our time have decided they need to turn the debates into yet another episode of this epic reality show.

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“The stage is set for the candidates to take on hot-button issues,” said the voice-of-God announcer midway through his introduction to the end of the world. Only the stage wasn’t set for that. It was set for some hot and sweaty fisticuffs.

The first night of Democratic debate featured CNN’s best effort to goad moderates into attacking progressives, and they obliged. The second night featured all the candidates at a Democratic donnybrook: men versus women, white versus black, old versus young, centrist versus liberal.

They say that you shouldn’t wrestle with pigs because you both get dirty and the pig likes it. After two nights of debate, the only figure who could have enjoyed the spectacle was nowhere near the stage.

If anyone loved the debates this week, it was the wrestling fan in the Oval Office who normally says he hates CNN.