To come out for remain now would be a natural move for Labour. It is the manifest will of its members; it is the overwhelming preference of young people (80%), who also by wild coincidence – or is it? – favour Jeremy Corbyn. It is the ardent desire of environmentalists, feminists and most trade unionists. Brexit is a Tory shambles; it has capsized all other government business. The political capital to be gained from shaking it off is almost unimaginable. A Labour party that campaigned for remain and won would become, de facto, the party of government. So why has Corbyn chosen this moment to reaffirm plans, in an interview with the Guardian, to lead Britain out of the EU if an election is called and he wins?There are three factions held responsible for the Labour leadership’s dogged refusal to come out and make the case its supporters believe in: the first is the electoral pragmatists, figuring remainers will vote Labour anyway, having nowhere else to go, so the party should chase leavers. But this is not a true picture of the data as it stands today – 193 constituencies that voted leave have changed their minds, and there are now 422 seats backing remain. Brexit as an issue has slipped in saliency for every voter except Conservative ones, so even those who still back leave put it way below other issues, such as universal credit and the NHS. The margin by which people back remain over Theresa May’s deal is reaching a scale of majority never before seen in this debate. ‘A Labour party that campaigned for remain and won would become de facto the party of government.’ Photograph: Dave Higgens/PASecond, there’s the “Bennite” tendency, the group that has disliked the EU on principle since the 1970s and damn sure isn’t going to change now. Even Tony Benn, if you watch his 1975 debate against Roy Jenkins, is not as Bennite as all that: he opposed the creation of institutions not directly answerable to voters. But he would have recognised immediately that you don’t restore power to citizens by disappearing down a Tory sinkhole where maternity leave and insulin are last century’s luxuries. The key voice in this group is probably Len McCluskey’s – still warning of the unimaginable dangers of a second vote, still insisting on the first as a definitive and final iteration of democracy – but his interventions are not setting the party’s direction. Rather, they sound like the expressions of a frustrated desire for dominance over a democratised party.Third come the hardcore Lexiteers: slash-and-burn communists who relish the coming upheaval as the crucible of true radicalism, who think of the EU as a neoliberal conspiracy. I know this view exists; I’ve debated with its proponents. But Lexiteerism is quite niche, and it’s far too abstract to be the real block on the concrete decision that has to be made now. The anguished stasis that afflicts the Labour party is instead rooted in what remain represents. Both sides of the Brexit debate are very new. As ideologies they stand only for whatever values you can glean from their proponents. So remain originated from Cameroonianism: shallow (can you really be bothered to exit?); multicultural in the most bloodless, instrumental way (migrants are net contributors to the economy) and in hock to the interests of business and finance (what about the City of London?). Jeremy Corbyn, understandably, struggled to ally with this.After the 2016 result, it evolved. Pushing a second vote became a thinly coded way of attacking Labour’s leadership; remain became a conduit to a centrists’ party with the knights of the old order in charge (Peter Mandelson, Alastair Campbell); Europhiles were building a shack for the “politically homeless” (as Tony Blair, with marvellous hubris, described the British populace, bereft of his leadership). If this were the sum of the remain imperative, it would be completely natural for Labour to oppose it. Yet there is a deeper case. And if this were led by Labour and run by Labour’s base – its constituency parties, Momentum, union members, Another Europe is Possible – remain would win by the kind of resounding margin that this battle needs, if it is ever to be resolved.A positive vision for the future needs solid answers to urgent questions: climate change, austerity, the erosion of workplace rights, the rise of fascism. All of these feed into one another to create a sense of precariousness and threat, and all solutions involve cooperation across borders. The new remain movement must articulate a future in which opportunities and freedoms expand rather than retract, citizens’ rights ratchet upwards in a race to the top, revivified unions support one another internationally, a green new deal echoes across multiple governments, racism is answered robustly and migration celebrated, and the dreams of the EU’s founders – peace, reconciliation, solidarity, equality – are rediscovered.The EU is not Jean-Claude Juncker, it is not one man, or any dominant nation, or any single idea: it is the sum of the decisions made by its participants. If you’re reaching for the radical stars in your own country, by definition you want that for the rest of Europe. To be an ally, you have to participate.Every cause has bedfellows who you’d rather weren’t in your bed. It would be impossible to conceive an idea as destructive and illogical as Brexit that did not number, among its opponents, a good many voices who were only in it for the status quo, for the single market and the customs union. To assume that just because Labour centrists oppose leave, the left of the party has to vacate the territory of remain is a catastrophic syllogism. Tory fellow-travellers are also inevitable; it’s only because of the collective cowardice of the Tory party that there aren’t more Anna Soubrys and Michael Heseltines fighting for remain.Labour cannot bide its time waiting for some indeterminate future when these voices have died down. If Brexit represents the politics of decline – economic decline, dwindling international standing, insecure national identity – then remain can, and must, stand for the politics of revitalisation. It cannot do that without the full-blooded leadership of the Labour party; but nor can Labour stand for renewal and decline at the same time.Zoe Williams is a Guardian columnistPublished in Daily Times, December 26th 2018.