At the 2017 general election, owing to low expectations, Labour’s defeat resembled a victory. At the 2018 local elections, owing to high expectations, the party’s victory resembled a defeat.

Labour did not achieve the gains on 3 May typically required to be confident of forming a government at the next general election, let alone winning a majority. Voters traditionally use council elections as a cost-free protest against incumbents. As Neil Kinnock and Ed Miliband can testify, local gains do not inevitably translate into national ones. “We’re not pushing ahead far enough, we have to do better to win a majority,” Jon Lansman, the head of Momentum, told me.

Based on the BBC’s projected national vote share, Labour was merely tied with the Tories on 35 per cent. Outside general election years, this was the first time since 1988 that Labour had not finished ahead of the Conservatives while in opposition. Yet Corbyn’s team reasonably point out that they have been confirmed as contenders for power. The 2017 general election result was treated by some Tories as a freak occurrence. Once the electorate realised how close Corbyn was to becoming prime minister (2,227 votes), the Tories suggested, the public would recoil from Labour. But both the local election results and deadlocked opinion polls signify a new normal. The same Tories who boast that a Corbyn premiership is not predestined once believed that he would consign Labour to the electoral depths.

The leader’s allies cite several reasons for Labour’s modest rather than dramatic gains (it won 77 councillors while the Tories lost 33). Broadcasting impartiality rules helped Labour counter Britain’s predominantly right-wing press in the general election. But in advance of the local contests, the party’s main national policy announcements – free bus travel for under-25s and the promise of a million “genuinely affordable” homes – received little TV and radio coverage. Turnout in local elections is lower than in national ones, particularly among the young (Labour’s strongest age demographic). Finally, in Britain, one of the most centralised countries in Europe, councils cannot affect the social and economic transformation that Corbyn promises (government funding for local authorities has been reduced in real terms by 49 per cent since 2010). As a consequence, disillusioned voters have less incentive to turn out.

At the post-election shadow cabinet meeting on 8 May, Labour chairman and Corbyn ally Ian Lavery also warned that hostile interventions against the leadership by rebel MPs had not helped the party’s cause. Corbyn’s internal critics reply that no excuses should be required while Labour faces an enfeebled Conservative government that has held office for eight years, that is profoundly divided over Brexit, and that presides over crumbling public services, rising crime and a stagnant economy. But if the Tories are not losing, they are not winning, either. The local elections showed how both Labour and the Conservatives are struggling to revive past hegemony. Neither commands broad support in the country. Labour has not won a comfortable parliamentary majority since 2005; the Conservatives have not won one since 1987.

Labour’s problem is not, contrary to some reports, that it underperformed in London. The party achieved its best result in the capital since 1971 (winning 47 per cent of the vote and 21 of the city’s 32 councils). Though Labour failed to claim the Tory citadels of Wandsworth and Westminster, it secured its highest number of seats in these boroughs for 32 years.

Far more disquieting for the party was the swing towards the Conservatives outside “Red London”. The Tories won bellwether councils such as Redditch and Peterborough, and deprived Labour of its majorities in Derby and Nuneaton (the loss of Nuneaton in 2015 symbolised the end of Ed Miliband’s prime ministerial ambitions). In such Leave areas, the Tories’ support has been inflated by the collapse of Ukip – deprived of its raison d’etre by the Brexit vote.

Labour recognises, in the words of one Corbynite shadow cabinet minister, that it is close to “saturation point” in metropolitan areas. To win, the party must make advances in provincial towns (a point of agreement in the shadow cabinet meeting).

Lisa Nandy, the Labour MP for Wigan, is one of those who has thought most deeply about this issue. For too long, she told me, Labour had been a “city-centric” party. But she praised Corbyn’s recent establishment of a “community campaign unit” – designed to rebuild support in post-industrial areas. “The first major political party who can speak directly to towns in a way that resonates is going to win not just the next general election but possibly the one after that as well,” said Nandy, one of the co-founders of the Centre for Towns think tank.

Corbyn’s challenge is reminiscent of that of the SNP. The Scottish nationalists surpassed most expectations by winning 45 per cent in the 2014 independence referendum. But they have since struggled to make another great leap forward.

The consolation for Labour is that the local elections in England have, in some respects, weakened Theresa May. Corbyn’s modest gains make it harder for Conservative whips to warn recalcitrant Remainers and Brexiteers that rebellion will gift the opposition the keys to No 10. The Tories’ renewed swagger may also serve Labour well. William Hague, the former Conservative leader, once archly observed that his party had only two modes: panic and complacency. The frenzy that followed the lost Tory majority at last year’s general election was proof of the former. The self-satisfied assertion that we have reached “peak Corbyn” is proof of the latter.

Stephen Bush is away