The European elections are of historic importance. Dangerous rightwing parties are likely to gain support, led by the Brexit party. We need to defeat the far right, and confront the spread of racism and the threat of authoritarianism and violence. We also need a serious commitment to tackling climate change and inequality.

The Party of European Socialists has released a radical manifesto, much influenced by Labour’s 2017 general election manifesto. It is calling for an end to austerity, for a green transition, for a feminist Europe and a “Europe for the many”. If Labour were to take these elections seriously, this could help shift the political balance in the European parliament – with a transformative effect on the EU and Britain.

But Labour appears to be deliberately trying to lose the elections on 23 May. The problems are both political and organisational. The political problem is that Labour insists on sticking to its fudged position on Brexit despite the urgent demands of party members, Labour MPs from the right and left, and figures in the shadow cabinet such as Keir Starmer, Emily Thornberry and Tom Watson, for an unconditional commitment to a confirmatory vote on any deal. The current position satisfies no one, in the same way that Theresa May’s Brexit deal satisfies no one. The hardcore leavers will vote for the Brexit party. The remainers will vote for overtly remain parties.

Organisationally, Labour is putting virtually no resources into this campaign. There are very few leaflets and the candidates have almost no support – the party’s machine is focusing instead on the Peterborough byelection on 6 June. Apart from Starmer and Thornberry, no shadow cabinet members seem to be on the campaign trail – and even when they do appear, no press coverage has been arranged.

‘When Theresa May’s deal was defeated by a huge majority in January, Labour had an incredible opportunity to demand a new public vote.’ The Tory frontbench during the defeat of May’s Brexit deal on 15 January. Photograph: UK Parliament/Jessica Taylor/PA

So why is Labour making such a historic mistake? To judge from public statements, the leadership believes that Labour’s poor showing in this month’s local elections proves simply that the public wants us to “get a deal done” on Brexit: the leadership also argues that their ambiguous approach to Brexit in the 2017 election helped them win voters. Actually, Labour’s 2017 success depended on people believing that it was fundamentally a remain party despite tactical ambiguity on Brexit. And regardless of the suggestion that the public simply want the political class to get on with Brexit, polling shows that a large portion of the public now wants to stop Brexit. There are, of course, hardcore voters who want to leave no matter what, but they have mostly already shifted to Farage and his Brexit party.

The tragedy is that Labour’s current position is contributing to the Brexit stasis. When the prime minister’s deal was defeated by a huge majority in January, Labour had an incredible opportunity to demand a new public vote. Had it done so, there would have been the chance to stop Brexit and even have a Labour government by now.

But if the Brexit party come out on top in the European elections, it is going to be much more difficult to stop the Brexit momentum.

Is there time to recover and move away from the brink? Labour is still the only party that can bring leavers and remainers together – and not through a vague attempt to triangulate with Brexiteers. It must take a firm position on remaining in the EU and combine this with a strategy to reform Europe and to end austerity: this would tackle the root causes of Brexit.

The remain parties, at least the Liberal Democrats and Change UK, merely offer a return to the status quo. The only way to take votes from the Brexit party is by making a credible commitment to employment, housing, and public services – and by refusing to pander to racist sentiment.

There is still a way for Labour to stop this Brexit juggernaut. If it ends the talks with the government, calls for a confirmatory vote on any deal and throws the well-oiled party machine into the election campaign, it is just possible that we can avoid the total meltdown that would result from the Brexit party triumphing on 23 May.

Will this be enough to restore the reputation for principle and honesty that prompted so many people to support Corbyn and his team in the past? Labour must at least try.

• Mary Kaldor is a professor of global governance and director of the conflict and civil society research unit at the London School of Economics