If Labour wants to get its second wind, it has to abandon Corbyn continuity

The party cannot go forward with confidence to another election if it believes that no major adjustments to its manifesto will be required

In politics, as in martial arts, it’s sometimes possible to use an opponent’s strengths against them.

In 2017, Labour’s tactic of constructive ambiguity helped the party to attract both Leave and Remain voters, and delivered its best swing since 1945. In 2019, the same strategy gave the party its worst Commons representation since 1935.

There is at present a bitter and inconclusive argument about whether Labour’s neutral Brexit stance hurt (in the north and in working-class Leave constituencies) more than it helped (in the broadly richer south, big cities and university towns). Far too much energy is being expended on this issue, one that will be irrelevant come the next election.

The distraction is symbolised in the legal action that Labour MP Emily Thornberry is taking against her former colleague Caroline Flint, who lost her Don Valley seat to the Conservatives. Even by the standards of the usual civil war Labour descends into after a heavy defeat, this is an unusual, indeed unprecedented move. Ms Flint, as it happens, would be a fine candidate for the leadership, as Michael Gove mischievously suggests. Her loss is her party’s, too.

It might be for the best if the whole question of Brexit’s impact on the 2019 election awaits the verdict of the British Election Study and Sir John Curtice. It is unlikely to be settled conclusively by spats, whether in court or on Twitter.

As an obstacle to Labour unity, Brexit should soon start to dissipate. In a matter of weeks, the UK-EU withdrawal agreement will be concluded. Talks about future economic and security cooperation will drag on for many years, no matter what Boris Johnson claims or legislates; but there is going to be less and less point identifying as a Leaver or Remainer in the coming years. Labour, in that sense, should forget about Brexit.

That does not, of course, mean that the rest of the programme Labour presented at the last election would have delivered a victory on its own – nor that it will necessarily do so next time. The left is right to argue that some of the policies, such as nationalising the railways, were individually popular. But taken together, the concatenation of commitments, some priced and costed, others not, failed to convince the electorate.

The Labour manifesto, then, was less than the sum of its parts, and the party cannot go forward with confidence to another election if it believes that no major adjustments to it will be required.

However, the assumed “Corbyn continuity” candidate, Rebecca Long-Bailey, seems set to adopt precisely that approach, taking with her the old Corbyn manifesto, staffers and union backing into a new chapter in political history – aided by the combative Angela Rayner, if she finally decides to be her deputy.

As loyal as these two flatmates and comrades are to one another, politics is a ruthless business, and history shows that such friendships do not always survive its strains and stresses. The uncomfortable truth is that the more pragmatic and assured Ms Rayner would be a better candidate to top the ticket than Ms Long-Bailey, who seems far too rooted in the failures of the Corbyn experiment. A neat answer would be for both to stand for both jobs (and thereby inoculate against Blair-Brown style tensions).

In other words, it may not be too late for Ms Rayner to remove herself from whatever provisional commitments she may have made, since there is much more at stake than her friendship with Ms Long-Bailey. Labour could not survive in anything like its present form after another drubbing at the polls. A grisly prospect for Labour supporters – such a defeat would represent the party’s fifth successive loss at a general election. The Conservative share of the vote will (probably) have risen; the parliamentary party may be well below the 200 seat mark; and the vulnerable folk Labour claims to want to help will have lived under a Tory or Tory-led government for 14 years. That is nothing to be proud of. At such a turning point, friendships and loyalties should be of little consequence.

A Labour Party run out of most of Scotland, Wales, the north and midlands, and reduced to rump of strongholds in Liverpool, Birmingham, London, Manchester and Leicester has no right to pretend to be a contender for government.

It is still early days. We have seen no leadership manifestos; heard no keynote speeches; seen little polling; and not had the candidates fully tested in the new Commons nor the TV studios. Lisa Nandy, Dawn Butler, Sir Keir Starmer, David Lammy, Jess Phillips, Emily Thornberry – there is a long list of credible contenders for both leader and deputy, and many permutations of the “dream team”.

The combinations of deputy and leader that have worked best are ones where the geography, age and outlook are balanced. Neil Kinnock (Welsh, younger, leftish) and Roy Hattersley (Yorkshire, older, social democratic) worked well rebuilding the party in similar circumstances in the 1980s; Tony Blair and John Prescott finished the job and took them back to power in the 1990s and 2000s. They’re tough acts to follow.