This is a devastating result for Labour but this has been coming for some time. More than any other party, Labour has struggled with Brexit. Nearly two-thirds of Labour’s 2017 voters supported remain, almost all the MPs supported remain, but two-thirds of Labour’s constituencies voted leave. Brexit has split Labour much more than any other party.

But this outcome has its roots long before 2016. As early as 2010, voters steadily started to desert Labour. This wasn’t all about Brexit.

In the focus groups, polling and campaign visits the leave campaign did during the 2016 referendum, it was blindingly obvious that huge areas of the country felt, and had been, ignored – and were rarely considered in a political conversation dominated by the concerns of Labour’s friends in London, which inevitably became parochial and patronising to the rest of the country.

In the years since the referendum, Labour’s right became fixated on stopping Brexit while the left became absorbed in the pursuit of a socialist programme under the control of a middle-class Marxist clique. Inevitably the divide between Labour and its fair-minded voters in rural communities widened to a vast chasm, and nobody cared.

The increasingly ideological left and right factions of Labour could not talk to voters whose frame of reference is fairness and common sense. To advocate a second referendum while campaigning to rubbish the outcome of the first may appeal to voters in London, but strikes many millions of other Labour voters as deeply unfair. And not just leave voters either. Remain voters outside the capital differ from their metropolitan counterparts. Most are not culturally wedded to the EU, as Labour’s remainers seem to be. They are pragmatic, reasonable and accept the referendum result, and could see what many leave voters were concerned about, even if they themselves voted the other way.

Labour has a London problem. Its leading remainers and leftwing ideologues both see the world through the eyes of a north London elite, and that distorts their view of the wider country. They gazed with disdain at working-class communities when these voters were Labour’s people and deserved respect.

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These communities are also the backbone of the country. Hardworking, proud of their skills, confident in their ability and dismissive of protectionism. They don’t want a handout but they do want good public services, there when they need them, and they want the same opportunity for their children to succeed as anyone else.

In rejecting Labour at the polls, these voters also firmly rejected the anti-Jewish racism that has taken root in the Labour party – something Labour’s left and right are still unwilling to do. Many moderate MPs could have forced the party’s leadership to act but did not. They seemed to shut it out of their minds, perhaps thinking it was a price worth paying to stop Brexit and stop Boris Johnson. Others seemed to simply lack the courage to act, even when Jewish MPs were hounded out of the party. This failure marks a dismal and shameful period in Labour’s history; it will be hard for Labour to recover from here.

Things can be put right but only if Labour stops trying to overturn the 2016 referendum. It is time to start treating voters outside London with more respect. It is also time to reject ideology and extremism and to take a stand squarely in the nation’s centre ground, championing enterprise and aspiration as well as strong public services; in short abandoning the ideological delusions of Labour’s private-school Marxists.

Above all, it is time for Labour to take a long hard look into its soul and to accept that anti-Jewish racism is and always has been embedded in the ideology of the far left and that moderate MPs share blame because they have allowed racism to spread like a disease in Labour’s ranks.

These are not problems to be solved by changing Jeremy Corbyn for another leader. Labour must eject the entire sectarian left from control of the party, and equally reject the temerity and blinkered obsession with remain of the Labour moderates who tolerate what Labour has become.

There needs to be radical change on both the right and the left of the party that brings Labour back into the moderate mainstream and purges anti-Jewish racism from the party for good. Until that happens Labour will not be fit to govern again.

• Gisela Stuart was the Labour MP for Birmingham Edgbaston from 1997 to 2017