I’ve always hated “Irish jokes”. Having an Irish mother, I’ve always been aware how they were used to denigrate Irish people and undermine the cause of Irish nationalism. There’s one joke, though, I’ve always enjoyed. It’s the one where the guy asks the Irishman for directions, to which he replies: “Well, if I were you I wouldn’t be starting from here.” It’s stuck with me because it offers a real life lesson that I find myself regularly referring to.

Back in the 1980s and 90s, it’s a lesson I should have heeded, as I argued and canvassed for a socialist Labour government when, in hindsight, it was clear that British voters had been wowed by Margaret Thatcher’s strong leadership and populist policies. For my arguments to get through, I shouldn’t have been starting from there. People such as Tony Blair and Alastair Campbell recognised this and modified Labour’s message to resonate with these same voters to spectacular effect.

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Yet, seeing Campbell announce this week that he’s given up on the Labour party, mainly because under Jeremy Corbyn it won’t go all-out remain, I couldn’t help wondering if he shouldn’t also take heed of that Irish lesson. Because if you want Labour to be a pure remain party – against the wishes of so many of its marginalised, traditional voters, particularly those working-class people in the north – then don’t do it after a referendum in which those same voters had the once-in-a-lifetime chance to actually make their vote count. Don’t choose this moment to tell millions of long-standing party supporters that you’re ignoring their deeply held views.

I, like Campbell, am a remainer. I also still want to reverse Brexit. But you can’t stick two fingers up to a huge chunk of your voter base and not expect a negative reaction. It’s why he spent so many years triangulating in the 1990s, trying to work out a middle way. How ironic that Campbell now condems Corbyn for doing exactly the same.

Corbyn is facing far more flak for this today than New Labour did 20 years ago, and that’s because many on the right of the party don’t actually want to see him win power. (If you want proof, look at Stephen Kinnock’s stony-faced reaction, captured by a BBC documentary camera, as the news broke that Theresa May had lost her majority in the 2017 election.) Many of those in and around politics still yearn for the Blair-Brown era when they were close to power. They’re not worried about the damage Labour would suffer by going “full remain”: an election defeat would merely hasten the day when the hated Corbyn steps down.

Play Video 0:44 Jeremy Corbyn: Labour supports a general election – video

Others say that now Boris Johnson has energised the hard right and united his cabinet over no deal, Corbyn must do the same – but for remain. This is nonsense. Johnson has already seen the damage caused by his rash decision-making. He’s boxed himself in by refusing to talk to European leaders until they ditch the backstop; he’s been slapped down by Nicola Sturgeon and learned that his stance is boosting the cause of Scottish independence; he’s faced angry Welsh farmers whose livelihood is threatened by no-deal tariffs; and he’s gone to Northern Ireland, where he’s been told that the peace process is at risk. And in Brecon and Radnorshire he’s tasted defeat after just a week in office, losing an 8,000 majority. Far from rallying supporters, his Brexit stance has just piled up his problems. He can’t even rely on the party’s hardcore Brexiteers to support any deal he might achieve with Europe.

One thing I do appreciate about Johnson, though, is his optimism. I’m an optimist too. In fact, the more I see of him, the more optimistic I get.

An early election – before we’ve left the EU – looks ever more likely. And it will be a choice between Johnson’s no-deal Brexit, and Labour, which has pledged to keep remain on the table but while still showing a sensitivity to leave voters. The precise stance depends on the election’s timing (as it must), but it’s clear that Labour is against no deal, and open to the possibility of negotiating a Labour Brexit, while promising a referendum on any deal that is struck. I’m no fan of a Labour Brexit, but, like I say, I wouldn’t be starting from here, and like it or not a majority of people voted for us to leave the EU.

That policy didn’t work in this year’s European elections, when it paid to have a clear message on leave or remain. Labour finished third, behind the Brexit party and the Liberal Democrats, a result that freaked out many Corbyn supporters. But these elections are notorious for being a repository for protest votes. The election was a proxy referendum, people voted along Brexit lines. There was no nuance. The policies that have made Corbyn so popular were not on the ballot: anti-austerity, support for public services, renationalisation, and fairer taxes for the richest. In a general election, the voters would face a simple choice: back Boris Johnson and the no-deal extremists, or back Labour and the chance to remain.

Facebook Twitter Pinterest ‘Others say now that Boris Johnson has energised the hard right and united his cabinet over no deal Corbyn must do the same – but for remain. This is nonsense.’ Photograph: Reuters

Of course, if it’s all so rosy, people will ask why the party isn’t way ahead in the polls, especially against this divided and useless government. But now, with the nation in crisis, it’s not that easy to forge ahead. It could just as easily be said: if remain is so great, why isn’t the demand for a People’s Vote way ahead in the polls, especially set against such divisive and useless Brexit negotiations for the past three years?

And I’d also say: cast your mind back just two years to a divided opposition party 20 points behind in the polls, which under Corbyn all but made up the gap in a few short weeks of general election campaigning. The situation may not be exactly the same today (let’s face it, Johnson will be a far better campaigner than May, though, like her when she called the election, he’s had the almost undivided loyalty of the national press so far). But he is untested in a battle for mainstream voters.

The last time the Tories won an election – the only time they’ve won in the past 27 years – they had a great soundbite that struck home in the last few days of the 2015 campaign: Labour, in alliance with the Scottish National party, would “bankrupt Britain and break up Britain”. Today, who would break up Britain? Johnson and his insistence on a hard Brexit that risks Scottish independence and Irish reunification. Who will bankrupt Britain? Again, Johnson and his no-deal tactics, which the Bank of England has warned would lead to an “instantaneous shock” to the economy.

An election victory is no easy feat, it never is, but to those who genuinely want a Labour victory, do not lose hope. In 2014, at the previous European elections, the Conservatives came in third place. Within a year, they were voted into government with a majority.

Maybe here’s not such a bad place to start from.

• Joseph Harker is the Guardian’s deputy opinion editor