Momentum said it believed in grassroots democracy – then it put just one candidate on a ballot paper

This version Corbynism resembles a kind of left-wing Blairism: good at knocking on doors and parachuting candidates, but bad at building a mass movement worthy of the name

This Labour leadership contest is unique in the party’s history. It is the first time that the Labour left has had to manage a succession, albeit in the wake of Labour’s worst general election defeat in almost a century. Britain, meanwhile, is leaving the European Union just a few weeks into the leadership election timetable. The factional politics of the contest are also unusually unclear, with some high profile figures on the left saying they will back Keir Starmer, and the Corbyn-sceptic wing of the party split between multiple candidates.

For all the many views on offer, one part of the party will be excluded after former candidate Clive Lewis failed to gain enough MP nominations to reach the next stage of the contest. The political tendency Lewis ran to represent is a growing one, both rooted in the left of the party and committed to internal democracy and a culture of pluralism. And it had the best claim to be the inheritor of the “new kind of politics” promised in the heady summer of 2015.

Lewis’s short-lived campaign showcased an alternative conclusion to the Corbyn project. It combined a radical economic programme geared towards decarbonising the economy with a promise to give members control of the party.

Lewis ran on a manifesto that promised to defend free movement and migrants’ rights and to challenge, not accommodate, the narratives behind Brexit. Taken together with radical new ideas on digital rights, constitutional change and the promise to put Labour at the centre of a broader, decentralised social movement, Lewis seemed to offer a genuinely modernised left-wing Labour Party.

Many members sympathetic to Lewis now face a dilemma. Keir Starmer is from the soft left, but his campaign is now backed by the Labour right. Many centrist activists and MPs have put their weight behind Starmer as the man to undo the left’s advances under Corbyn. Those who fought so hard to get Corbyn elected and to make a success of his leadership must be cautioned by the possibility that Starmer’s centrist backers could be right about that role. And if your main criticism of Corbyn was his fudge on Brexit, then the same charge must also be levied at Starmer – he was one of the architects of the complex sequence of policies which kept “all options on the table” while never really picking any of them.

Rebecca Long-Bailey represents, as far as anyone can tell, continuity Corbynism of the one-more-heave variety. Over the past four years she has been relentlessly loyal, but to be a credible successor she must offer a sharp diagnosis of what went wrong. This would mean being honest about the fact that the democratic promise of Corbyn’s leadership was never delivered, and that the party’s rightward drift on immigration – with the 2017 manifesto abandoning free movement – made beating the Tories’ narrative on Brexit almost impossible.

Between the summer of 2015 and the 2019 general election, “a new kind of politics” gave way to a culture of command and control within the Labour Party. Critical friends of the Corbyn leadership found themselves frozen out, characterised as wreckers undermining the left; and landmark policies like open selections were ditched to keep union leaderships happy. At every level of the party, a culture of loyalism, bullying and an intolerance of dissent has set in.

In local Labour parties and Momentum groups across the country, undecided party activists and supporters of Clive Lewis have spent the past few weeks being bellowed at to get back in line. This is, to put it mildly, counterproductive.

The manner in which the machinery of the Labour left has closed ranks behind Long-Bailey has done nothing to allay concerns. Today’s news demonstrates this powerfully. Momentum – once the organisation promising to champion grassroots democracy – has agreed to ballot its members on who to back, but has only given them one option to vote for. This version of Corbynism resembles a kind of left wing Blairism: good at knocking on doors, stitching up committees and parachuting candidates, but bad at building a mass movement worthy of the name.

Democratic socialism is what we need, but you can’t leave out the “democracy” bit. To win back the trust of many Labour members, Long-Bailey must break not only with many of the prominent individuals and cliques who ran Corbyn’s office, but with the whole political tradition they represent.

The basic maths of this leadership contest are stark. In 2016, Owen Smith got 38 per cent of the vote, and those votes are guaranteed to transfer to Keir Starmer. To win, Long-Bailey must consolidate the overwhelming majority of Jeremy Corbyn’s voters, and that means including people and recapturing the spirit of 2015, championing a principled stance on issues like immigration, movement-building and democracy.

In the end many activists may feel obliged, simply as a matter of duty, to give Long-Bailey their vote to keep some version of the left in power. If that is the strategy, it doesn’t sound like a winning one.