Never interrupt the enemy when he is making a mistake,” tweeted Labour’s international trade spokesman, Barry Gardiner, last week, quoting Napoleon. Like most of Labour’s frontbench he had opted not to engage with Theresa May’s post-Salzburg strop, preferring to let the Tories tear themselves apart unmolested.

But Napoleon also said that when the enemy is in disarray you should send in the cavalry pronto. With the Tories flailing, it is time for Labour to unleash a two-pronged political offensive: it should give a clear commitment to a Norway-style deal, and promise a second referendum to ratify it if achieved.

Though it edged towards this in a composite motion agreed on Sunday night, the position is still frustratingly unclear.

Labour’s refusal to cement its desired end state for Brexit was defensible until July. Jeremy Corbyn’s team wants, above all, to bring down Theresa May’s chaotic administration and get an early shot at government. If it achieves that, launching a radical project of growth and social justice, it could change the political atmosphere across the developed world.

But Labour’s leadership has struggled to understand that, since the Chequers deal fell apart in July, the Brexit issue has become the primary weapon to achieve a Labour government. This is partly due to the memory of 2017. In the last election, Labour activists found that as long as they assured people Brexit would happen, the issue evaporated on the doorstep, allowing them to talk about healthcare, local services and employment rights.

But if, as has been suggested, May’s advisers are planning a second snap election, this would unleash – yet again – a “back me or sack me” campaign focused around Brexit. With the looming possibility of food and medicine shortages, and a deranged tabloid press revelling in the prospect of no deal, it would be hard for Labour to distract voters from the central issue a second time.

In addition, the EU’s flat refusal to discuss the Chequers proposal signals to Labour, just as curtly as it signalled to May, that there are only two options: a Norway-style deal that leaves Britain inside the single market, and a Canada-style free trade deal. Under intense pressure from members dissatisfied with the current line, Labour delegates have agreed to table a resolution committing Labour to “full participation in the single market”. That is significant.

Last December, the Institute for Public Policy Research presented Labour with a white paper advocating Swiss-style “alignment” with the single market, rather than participation. As with May’s Chequers plan, the IPPR wanted Britain to align voluntarily with some single market rules, but diverge from others in order to promote growth and social justice. Though the shadow cabinet refused to endorse the IPPR plan, the document is the closest Labour has ever come to drawing up its own version of Chequers.

But the Salzburg summit showed that a voluntary alignment option is no longer possible. May has wasted two years, and expended almost all the UK’s negotiating capital, only to get her version of it rejected. Labour’s new conference motion, committing the party to participation in the single market, appears to recognise that.

Corbyn’s strategy to date – of spelling out red lines and opposing solutions that crossed them – was always designed to allow Brexit-supporting Labour voters to learn by experience how treacherous the process would be. The Tories had told them that leaving would be easy; it wasn’t. They told them the new treaties would be done and dusted by March 2019. They will not be. They assured voters there would be no downsides to a no-deal solution. Now they urge voters to stockpile food in case it happens.

The gameplan worked up to a point. May’s chaotic negotiating stance has eroded popular support for Brexit, though not decisively. But the process of learning by experience now has to be supplemented with a positive vision, reinforced by Corbyn and Keir Starmer spelling out a clear Brexit proposal of their own.

My position on Brexit has always been a compromise between principle and what’s needed to assemble a voting coalition to put a leftwing Labour government in power. If it had been possible to achieve a leftwing Brexit, I would have supported it: the Lisbon treaty is a machine for destroying jobs and growth, and is stoking disillusion in democracy. But the real-world forces pushing for Brexit in 2016 were always those of xenophobic nationalism, and their project was an even more deregulated and polluted Britain. So I campaigned on remain and reform.

Once we lost, the challenge was how to craft a bespoke deal that respects the result, allowing working-class communities to move on from the bitter arguments that had dominated their public spaces. But after Donald Trump’s election victory, the options for such a deal narrowed.

Paul Mason

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