It is one of the oddities of this weirdest of election campaigns that the issue that helped give the Conservatives an 80-seat majority in 2019 has barely been mentioned. As far as the main parties are concerned, Brexit is a done deal. The decision has been made. Time to move on. To be sure, much has happened since 2019, most notably a global pandemic, a cost of living crisis and the brief – yet drama-packed – premiership of Liz Truss. Making ends meet features more prominently in voters’ lists of concerns than whether the UK should rejoin the single market. Even so, the fact that the UK left the EU since the last election matters. It matters because Brussels can no longer be blamed for the UK’s problems or the failure of UK politicians to deal with them. The EU can’t, for example, be fingered for record net migration numbers in 2022. Those are entirely due to decisions taken at Westminster. The likely scale of the Conservative defeat on 4 July will be the result of voters holding the government fully to account for rising prices, falling living standards and a failure to deliver on levelling up. There is no hiding place, and that’s good. Many of those who voted leave in 2016 because they felt ignored and marginalised still feel ignored and marginalised. They gave the Tories a chance and they blew it. From next week, they will almost certainly be able to see whether Labour can make a better fist of things. Keir Starmer has been on quite a journey since he was the shadow Brexit secretary under Jeremy Corbyn, pressing for a second referendum. He has not just ruled out rejoining the EU but has also said there will be no return to the single market or the customs union. Instead, Labour wants to smooth out the wrinkles by negotiating a better trade deal with the EU than the one Boris Johnson secured. It remains to be seen whether Starmer’s fellow MPs and Labour party supporters have come on that journey with him, because for the most part they are solidly anti-Brexit and pro-EU. That has not always been the case, and there was a time in the 1970s and early 1980s when, under Tony Benn’s influence, Labour was the more Eurosceptic of the two main parties. But after Labour’s drubbing at the 1983 election there was then a shift towards a more pro-EU stance amid hopes that Brussels-style socialism offered a way to circumvent the policies of Margaret Thatcher. To say the least, the party is not entirely comfortable with Starmer’s decision to rule out rejoining the EU. Labour’s Brexit strategy was summed up by Starmer on one of the few occasions the issue has surfaced during the campaign – a BBC Panorama interview with Nick Robinson. “If you look at the problems for growth over the last 14 years, they were there, or many of them were there, before Brexit, so the idea that the sort of single silver bullet is simply the relationship with the EU is not something I accept.” Starmer is right about this. The parts of the country that voted most strongly for leave were those that saw the sharpest rises in unemployment in the 1980s and the biggest increases in incapacity benefits as attempts were made to massage the jobless figures down. They had the heaviest reliance on the tax credits to top up poverty pay, and they bore the brunt of the welfare cuts introduced by George Osborne after 2010. As the Institute for Fiscal Studies has noted, progress towards the 2030 levelling up goals set in a 2022 white paper has been “glacial” and in some areas the UK has gone backwards. Political developments on the other side of the Channel are helpful to Starmer, because he can point out to his critics that the EU is not exactly a haven of contentment and prosperity, and hasn’t been for some time. There is some irony in the fact that the left’s love affair with Europe began in the 1980s at a time when the EU’s economic performance took a marked turn for the worse. Then in the 90s, the single currency was supposed to deliver faster growth and greater shared prosperity. Instead, as the growing support for populist parties shows all too clearly, monetary union has been accompanied by economic stagnation and rising inequality. Voters in the UK’s industrial heartlands are not the only ones who feel marginalised and ignored: the same sentiments are widespread in struggling parts of Germany and France, particularly among young voters. Starmer may find that improving trade links with the UK is not top of the EU’s list of priorities. Instead, the pressure is on him to use all the tools at his disposal – tax, procurement, state aid, nationalisation, subsidies, skills, control of migration – as part of an activist industrial strategy designed to boost growth and narrow regional divides. This was what those on the left who supported Brexit called for in 2016 and there is now even more of a need for such a strategy. Doubtless, some will say a Brexit growth strategy is an oxymoron. Others will say – with some justification – that Labour’s growth strategy is too small to make a difference. Some may even be quietly hoping for Labour to come a cropper because it will ease the way to rejoining the EU. But there is no real difference between Labour’s growth strategy and its Brexit strategy. If one fails then so does the other. Larry Elliott is the Guardian’s economics editor