FAR from enhancing Labour’s appeal to its lost legions of voters, the defection of the former speaker of the house from his lifelong Tory politics to membership of the Labour Party is another sign that under its present leadership that the party has lost its way.

John Bercow’s ideological journey is from student adherent of the rabidly racist Monday Club to an indeterminate spot somewhere between the Liberals and the right wing of Labour.

His explanation — “I am motivated by support for equality, social justice and internationalism. That is the Labour brand” — needs decoding.

Equality and social justice are terms sufficiently subjective to be the avowed objective of almost every political tendency, while in this context “internationalism” is code for global free trade on monopoly-capitalist terms, liberal interventionism and membership of the European Union.

Naturally, Bercow is with the majority in thinking that the government needs to be replaced and the obvious reality “that the Labour Party is the only vehicle that can achieve that objective” — is something we can all agree on.

The point, however, is on what basis can Labour become the government.

The substantial stay-at-home Labour vote in the Amersham and Chesham by-election — allied to a wholesale defection of the more fastidious Tory voters — has resulted in life being breathed into the near-dead body of the Liberal Democrats.

Turnout was broadly comparable to the 2019 general election.

The Tories lost their majority of 16,000, and Labour lost the best part of 7,000 votes to poll 622 — a catastrophic collapse from its second place in 2017, with this time round the Greens the most likely beneficiary.

Like Liberal leader Ed Davey’s heavy hints that Lib Dem voters in the forthcoming Batley and Spen by-election might consider voting for the Labour candidate, this is mood music for an unprincipled electoral lash-up with a party that just a few years ago formed the neoliberal austerity administration of Nick Clegg and David Cameron.

This is a moment of danger for Labour. While Bercow is absolutely right that only Labour can form an alternative government, it will not be able to do that without appealing to a very wide coalition with a mobilised and enthused working class at its core.

By-elections at the moment seem to signify that voters are as much concerned to deliver a judgement on the opposition as the government.

The incontrovertible evidence is that a substantial section of Labour’s core constituency is profoundly unhappy and has joined that wide section of working-class voters who see no reason to vote for anyone.

The lesson driven home by the experience of Westminster Labour’s sabotage campaign against Jeremy Corbyn’s leadership is that neoliberal economic polices and liberal interventionism are already overly represented.

What badges itself as the “progressive” centre is actually a right wing already deeply embedded within Labour.

What saves Labour from “Pasokification,” what distinguishes it from the failed and failing social democratic parties of Europe is precisely its relationship to the organised working class in trade unions and its still substantial support from many working people and important sections of the professional and public service-orientated middle classes.

A so-called “progressive alliance” can only be on the basis of a Lib Dem veto over key policies for public ownership, a genuinely progressive tax regime to make the corporate rich pay, free tuition and trade union freedom — on which these people have established a reputation for duplicity and double dealing.

It would be a disaster for Labour to sink into a swamp of such “centrism” — precisely the point at which the Tories are making a relatively successful pitch for parts of the working class.