The mood at the Labour Party Conference this year was markedly different from last year: after Jeremy Corbyn’s victory was announced in Brighton in 2015, there was a huge amount of jubilation among delegates, while many MPs and political advisers wandered around the bars at night with bereft expressions. In Liverpool this week, the most that supporters could muster was temporary relief as they wondered where the attack would come from next. At private parties, MPs looked resigned as they gossiped with journalists.

A lot of people pointed out that the politicians, journalists and academics who have repeatedly called for Ukip voters to be not attacked, but understood, aren’t so generous when it comes to that other recent populist movement, Momentum.

A few days before the conference, ‘Momentum Kids’ was announced: a scheme proposed by two single mothers, Natasha Josette and Jessie Hoskin, who wanted to find a way to help people with children get involved in local activism. The idea isn’t new – many left-wing movements try to have creches at day conferences – but it was a way of providing formal childcare for activists. The two women were largely ignored in the histrionic reaction, though while Josette was in Liverpool someone describing themselves as a Daily Mail reporter approached her neighbours, former partner and accountant. Momentum Kids was variously compared to the Hitler Youth, described as Stalinist, said to have been cooked up by posh boys and nicknamed ‘Tiny Trots’. What it actually involved was a small programme of activities, including Brazilian jiu-jitsu training and singing lessons, to give children a break from panel discussions and their parents an hour or two unencumbered.

Momentum held its conference fringe events in a former church hall, decked with banners that memorialised the deaths of black people in police custody, or carried messages about social justice, Hillsborough, climate change. A local co-operative bakery sold pies and coffee alongside left-leaning booksellers. Journalists, cameras in hand, examined the merchandise for evidence of Momentum’s alleged cultishness or violence, usually settling on a ‘Still Hate Thatcher’ T-shirt.

This led to wariness among the speakers, though many of the journalists and pundits who came grudgingly accepted it was a good effort, more welcoming and enjoyable that the rest of the conference. Organisers were waiting for the hatchet jobs to arrive; the best the Express could do was post a video in which someone referred to Corbyn as ‘their king’.

Eventually the problem came from within: Jackie Walker, Momentum’s vice-chair, said that Holocaust Memorial Day only commemorates Jewish deaths in the Holocaust (it doesn't), and that she hadn’t ‘heard a definition of antisemitism that I can work with’. Momentum’s steering group is likely to oust her when it meets on Monday.

Before the conference, I repeatedly asked Corbyn’s critics what their plan was going to be after he won the leadership contest. At first, they said it wasn’t certain that Owen Smith would lose. That lasted maybe three days. Then they said: ‘We stand someone else again and again.’ (They seemed to take a certain amount of glee in the fact that both Corbyn and John McDonnell are older men, as though politics were mostly about endurance, and the long game consisted of grinding down older, weaker opponents.)

But on Saturday, after Corbyn’s re-election on an even bigger mandate than last year, it was clear there wouldn’t be another leadership challenge just yet. Chuka Umunna told the BBC it was a shame that immigration had not been a bigger issue in the leadership campaign. Rachel Reeves followed, channelling Enoch Powell as she said there were ‘bubbling tensions’ in the country that ‘could just explode’. The thinking behind this tactic is straightforward: immigration is something that Corbyn will not budge on; the right of the party can then claim he is immovable, rather than principled, and out of step with public opinion, as if public opinion were a monolith, rather than changeable and influenced by political arguments and media coverage. Corbyn’s critics' thinking may be straightforward, but that doesn’t mean it’s coherent: they also say he isn’t pro-EU enough and Labour should chase the 48 per cent of people who voted Remain in the EU referendum.

Still unresolved is the central tension between the membership and the Parliamentary party. The MPs argue that a mandate from the members does not mean someone is electable: this is true. But it isn’t clear that the MPs know better than the members what ‘electability’ looks like: Labour hasn’t won a general election for more than a decade, and most Labour MPs didn’t hold their seats in 2015 because of their innate electability. Barely anyone predicted the result of the last general election; many people thought the UK would vote to remain in the EU. Perhaps the rebel MPs will now accept that if they can’t convince their members of their candidates’ worth, they’ll also struggle to win round the public. But in the meantime, expect to see immigration as a conduit for attacking Corbyn.