US 2020: The end of Sanders and Warren's non-aggression pact could hurt the Left

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It’s a reminder of how placid these Democratic presidential debates have been that the best moment came when the candidates thought the mics were off.

As those on stage shook hands and relaxed at the end of Tuesday night’s clash Elizabeth Warren drifted towards her friend and fellow left-winger Bernie Sanders.

Mr Sanders proffered his hand, but it was not taken. “I think you called me a liar on national TV” uttered Ms Warren, face like thunder. She said the line twice before turning away.

That moment, an unplanned reaction to Mr Sanders’s denial that he once told her a woman couldn’t beat Donald Trump, was picked up by CNN’s hot mics and published last night. (Watch it here.)

It completed a phenomenal disintegration in personal relations between the two senators. It has also thrown the party’s left-wing into acrimony and uncertainty.

Mr Sanders and Ms Warren are placed second and third in national polling on who Democrats want as their nominee. Above them sits Joe Biden, the former US vice president. 

Both are carrying the torch for progressives. Both have very similar policy pitches, pledging to take on corrupt elites, adopt a wealth tax and give government-funded healthcare for all.

And for the last year, both candidates have had a non-aggression pact. Instead of attacking each other and hurting the Left-wing cause they have targeted their fire at moderates.

But with Iowa, the first state to vote, less than three weeks away and both chasing the same voters, enmity has arrived. The tensions emerged over the weekend but soon snowballed.

First a leaked cold call script showed Bernie’s camp was framing Ms Warren as an elitist. She responded by saying they were trying to “trash” her.

Then CNN reported Mr Sanders’s alleged ‘a woman can’t win’ remark from a meeting between the pair in December 2018, citing anonymous sources. Team Bernie called it “lies”.

Then Ms Warren went public to confirm the story; Mr Sanders denied it. When the pair met on the debate stage they stuck to their positions – prompting the contretemps at the end.

Aside from the intrigue of hearing politicians speaking when they think no one's listening, the row this late in the race could have real political repercussions.

Add together Ms Warren and Mr Sanders’s vote shares [35 per cent] and it is higher than Mr Biden’s [27 per cent]. In other words, a big chunk of Democrats want a major jump Left.

Throughout this race the progressive fear has been that their chances of victory are being undermined by two candidates splitting the vote, letting a centrist win instead.

Now both sets of supporters were digging in. Bernie fans were sharing images likening Ms Warren to a snake online on Wednesday night, according to the LA Times. Ms Warren’s backers were accusing Mr Sanders of misogyny.

The row could end up hurting the cause they both believe in. If one candidate struggles in the early states, will they drop out speedily and back the other? That feels less likely now.

The last thing the Left needs is a civil war. Mr Biden, sitting pretty at the top of the polls, must not believe his luck.