Remain is now a political identity that will shape Britain long after Brexit

A remainer was once defined as a voter who wanted the UK to stay in the EU. Then the term got looser, scooping up politicians who pledged to fulfil the referendum mandate while failing some other test of Eurosceptic rigour. The pass mark keeps getting higher. The self-appointed arbiters of True Leaver credentials will not even credit MPs who backed Theresa May’s deal, although it would have counted as a “hard” Brexit under the 2016 curriculum.

Boris Johnson’s version is palpably harder still. It prohibits the negotiation of anything too intimate with the EU in post-Brexit trade talks. If terms are not agreed with Brussels next year, a nasty cliff-edge comes back into view.

MPs who balk at that hazard will be cast as remainers, even as they rubber-stamp the rest of the package. This is how the Eurosceptic ratchet has worked over two decades, shifting Tory politics from a position where benefits of EU membership were undisputed to a place where belief in those benefits is seditious. The word Eurosceptic used to express wariness of further integration. Now it means someone who is not content to burn bridges but insists on also laying mines and barbed wire around the smouldering stumps.

Moderate Tories who enable that process, hoping one day to restore peace in their party, have learned nothing from recent history. The hardliners do not compromise, except as a tactical feint before upgrading their demands. They do not even accept total surrender, which is what a vote by any former remainer for Johnson’s Brexit indicates. They will pursue the defeated side until the very memory of a pro-European Toryism is extinguished. Labour MPs who lend their votes to that endeavour are ignoring a different history lesson – the one where a group of highly motivated, left-leaning voters remember and savagely punish a party that abets the Tories.

Europhobic fanaticism has broken the will of some remainers but radicalised the rest. Since Johnson became prime minister, I have felt gloomy about the UK’s future relations with Europe. But Brexiteers’ refusal to be magnanimous in victory and hysterical intolerance of dissent reeks of insecurity. Their constant dread of defeat makes me think it is still possible.

As a political project, remain has been a sequence of tactical, rearguard successes on a long retreat. MPs have imposed scrutiny when Downing Street wanted secrecy, but crafty procedural manoeuvres have not changed all that many minds in the country. They have been as likely to reinforce leave voters’ suspicions that an impenetrable establishment stitch-up is under way.

Outside parliament, the People’s Vote campaign has whipped up demand for a referendum, but that is an expedient to avert Brexit, not an argument why EU membership is worth saving. Many Europhiles find the thought of another bitterly fought plebiscite dispiriting, so they shrink from the policy printed on the banner under which they rally. Charismatic leadership celebrating the pro-European cause on its own terms is no more available now than it was in 2016.

The People’s Vote strategy judged that a referendum could only happen if MPs voted for one, and that required endorsement from the official opposition. The whole enterprise got tangled in Labour’s internal politics, marked by factional vendetta and paranoia. It has been hard to make a public argument that the UK belongs in the EU while still privately lobbying sceptics in Jeremy Corbyn’s office for permission to pose the question.

Labour’s ambivalence has been a gift to the Liberal Democrats, but Jo Swinson has not asserted her presence on the national stage. Her voice might carry further in a general election. It could also be drowned out by the traditional collusion of Labour and Tory campaigns to present the ballot as a binary choice.

Still, the two main parties will not find it easy simply to partition the remainer vote, even if the ballot comes after the UK has left the EU. Corbyn and Johnson would both like to shunt the conversation on to other matters, and there is a receptive audience for politics that isn’t about Brexit. But there are also forces that will keep pushing Europe back up the agenda. Tory leavers will not let it lie. Already they mutter about “securing Brexit”, by which they mean sustaining momentum through a transition period, hurtling towards the day of ultimate bridge detonation in December 2020. Their fear is that Labour’s pro-Europeans will escape the debilitation of Corbyn’s leadership and that a refreshed, united opposition will turn remain into rejoin.

That anxiety contains the recognition that Johnson’s deal is a sleight of hand. It sets up an interlude of stability in transition (while the UK passively sucks up new EU regulations) before the full impact of a hard Brexit is felt. Leave ideologues have utopian faith that all will come good in the end, but not before a period of job-shredding turbulence. They worry that voters will take fright as the reality of going it alone in a savage global marketplace comes into focus.

They should also worry about the cultural dynamics sustaining the anti-Brexit movement. The pro-EU electorate has been poorly served by the main English parties but, paradoxically, that has nurtured attachment to remain as an identity. In the absence of capable political representation, the cause has become a grievance – a lingering burn in the hearts of people who didn’t think about their status as citizens of Europe before 2016, but now resent having that citizenship, and all it represents, withdrawn.

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It is convenient for Brexiteers to dismiss these people as a metro-elite, snivelling over their crushed avocado on sourdough. But the caricature obscures awkward electoral and demographic facts. Remainers come in all ages, but their numbers swell in younger cohorts. They are more likely to live in cities, but they are spread all over the country. There are millions of them and they vote.

These are people who will shape the next generation of British politics and no sane party should be despising and alienating them. The material benefits of Brexit are remote if they exist at all, and the costs high. There will be an instant of gratification for leavers on the day of symbolic escape from Europe, and relief for the bored agnostics. But those feelings will, I suspect, be weak and transient compared with the anguish and loss felt on the other side. Leavers will not thank politicians for Brexit, not with the passion and persistence of the remainers who will punish them for it.

• Rafael Behr is a Guardian columnist