I’ve had a lot of conversations about Jeremy Corbyn with fellow Labour supporters. Well, arguments, really. A lot of the kind of arguments that devolve into apoplectic stammering, mutually hostile blinking, occasional tears and, in one case, mimes. Back during the 2015 leadership campaign, I angrily told a Corbyn-backing friend that his candidate would be an electoral disaster for Labour. In reply, he smiled and acted out setting off the plunger on a stack of dynamite. For a lot of Corbyn’s supporters, his victory was the moment to rip everything up and start again; to tear down all the apparatus of New Labour, and write a new origins story where Tony Blair never happened.

It didn’t quite turn out like that. For one thing, Corbyn the radical didn’t materialise: most of his policies could have sat comfortably in Miliband’s manifesto (if they weren’t there to begin with), and where his values did diverge from recent Labour history, they sometimes came as an unpleasant surprise to his base. Take, for example, Corbyn’s attitude to the EU, manifested in a Remain campaign to which he brought all the vigour and pep of an exhibit in Bodyworlds – no shock to Bennite old lags, but a grievous insult to the younger idealists of his coalition.

Yet with no major electoral tests, the Labour Party has maintained a rickety sort of stability despite the mass resignations of the shadow cabinet last summer. The shell is standing, but the supporting beams have collapsed. And now Theresa May has announced her intent to call a general election in June, we’ll see just how fragile the party is. Although an early election spares Labour the pain of the 2018 boundary changes, its terrible position in the polls – and the dire personal unpopularity of Jeremy Corbyn – mean there’s very little comfort for Labour. The party, which is my party, is looking at a catastrophe.

For Labour members (including me) who recognise how much of a liability Corbyn is, this is going to be a difficult campaign. One of the most compelling arguments against Corbyn’s leadership is that he’s toxic to voters; but clause 1 of the Labour rulebook commits members to “promote the election of Labour Party representatives at all levels of the democratic process”. So do we promote the election of Corbyn, however hopeless we know it to be, however much we know that promoting him injures Labour’s prospects at every other point? Or do we sit this one out, twisting our membership cards in our restless fingers?

But it’s not just that Corbyn is unpopular. It’s not even just that he’s incompetent – although you’re clearly in the realms of political imbecility when a moderately successful week of opposition announcements in the run-up to Easter brings supporters out in spasms of relief. It’s that he’s unconscionable. In the most serious possible way, it is morally intolerable to imagine Corbyn as Prime Minister. Corbyn, who has been responsible for an unparalleled abdication of opposition over Article 50. Corbyn, who has led the way in smirking denial of anti-Semitism within Labour, even while one of the greatest threats to the nation and the continent is the creep of the far right.

For those reasons, I can’t campaign for Corbyn. But we have to work for something to remain of the party after him, which means campaigning for those candidates who offer Labour a future. Maybe you’re lucky enough to have one in your constituency: you live in Birmingham Yardley and can vote for Jess Phillips, or Bristol West and can vote for Thangam Debbonaire, or to be honest most places that aren’t Islington North or Vauxhall (seriously, that’s enough Kate Hoey now). If you don’t, then find the nearest constituency with a candidate worth supporting, and volunteer. The 2017 general election is going to be a brutal one for Labour, but it can survive. The country still needs Labour, and Labour needs to become a party that deserves to govern again, one day.