“Welcome to our party, welcome to our movement. And I say to those returning to the party, who were in it before and felt disillusioned and went away: welcome back, welcome home.”

Those words, said by Jeremy Corbyn during his leadership victory speech in September 2015 seem predictable, innocuous and friendly. They are not.

What matters about political speeches are not their words but context and aims. After all, no politician is going to tell the nation they want it to be poorer and more unfair. Unlike some of his supporters, Jeremy Corbyn was never going to say, “Those who supported New Labour should bugger off and vote for another party.”

This one “welcoming home” the “disillusioned” is an example of Corbynism’s foundational article of faith, the truth it casts as self-evident and incontestable. This is that at some point between 1983 and 1997 the Labour Party abandoned its socialist principles and history for power. Listen to all types of Corbyn backers and you’ll hear versions of this belief. For Jeremy himself it happened even before 1983, his political mentor Tony Benn believed the fall of the Wilson/Callaghan government in 1979 was due to their dilution of socialist principle. Others, like Corbyn’s key lieutenant Jon Lansman, campaigned vociferously against Neil Kinnock’s shifts from the disastrous 1983 manifesto. Among many younger members who grew up in the twilight of the Blair and Brown government the article of faith is that Blair, and to a lesser extent Brown were usurpers who used the Labour banner to promote their own political project that abandoned Labour’s long held principles.

It seems both plausible and true, not least because Tony Blair wasn’t entirely unhappy with its promotion himself. The very name New Labour didn’t just imply a break with the past but stated it. Part of the Blair elixir for electoral success was a pitch to apolitical and centrist voters that included the idea the party wouldn’t place the interests and opinions of its more zealous voices above their own.

The problem is, it’s not true, and what once was a white lie with electoral benefits has become a toxic myth destroying the Labour Party, rotting it from within and ripping it apart. To see why, one needs to delve into Labour’s recent and distant past.

Firstly, New Labour was not the ‘neoliberal’ government of (un)popular lore. It massively increased spending on public services, introduced the minimum wage and tax credits, as well as many new programs designed to help the poorest including Sure Start and the Educational Maintenance Allowance. Blair’s pitch to the electorate — that he was a different type of Labour leader, was not entirely true — yes, he decided not to refight the battles of the 1980s in reverse as some wanted him to. Yet his pragmatic decision to focus on channelling funds to public services and modernising them rather than engaging in economic revolution, was very much within the Labour tradition. For those who’d contest this, I’d simply ask why, if this government made no difference, it is so important to protest against the removal of measures they introduced?

Even the great symbolic departure from Labour’s past — the scrapping of Clause IV requiring the nationalisation of industry, was not as much of a break as it seemed. The clause had long been a point of contention within the party, with then leader Hugh Gaitskell attempting to get it repealed as far back as 1959. His successor Harold Wilson, an astute manager of the party’s fractious factions, chose to keep the clause in place but other than an early nationalisation of the steel industry, stuck to rationalisations of existing state owned utilities (water, gas, buses, the Post Office), or rescue packages for companies deemed too important to fail (Rolls-Royce, British Leyland).

Wilson’s most famous speech, given at his last Labour Conference in opposition in 1964, sounds positively Blairite in its focus on modernisation.

“We are re-defining and we are re-stating our Socialism in terms of the scientific revolution,” Wilson said. “The Britain that is going to be forged in the white heat of this revolution will be no place for restrictive practices or for outdated methods … our future lies … in the efforts, the sacrifices, and above all the energies which a free people can mobilise for the future greatness of our country.”

If the Labour governments of the 1960s and 1970s’ exhibited pragmatism and modernisation rather than pure of heart socialism — then what about the revered Attlee ministry of 1945–1951? This did set a major program of nationalisation in train — it created the modern welfare state and the NHS, surely these are the first principles to which Corbynism promises a return?

A closer inspection of Attlee’s government however reveals it was a far more nuanced and complex entity than some of its eulogists would have us believe. Even as the modern welfare state was created, the term ‘austerity Britain’ was coined. Public expenditure in the final years of that iconic government was lower as a percentage of GDP than today (or at any time during the recent Tory governments). At the same time, Britain was reliant on loans from the United States (which came with contingencies on trade and modernisation of industry). In foreign policy Labour politicians were driving forces in creating Nato and the development of the nation’s nuclear deterrent — positions Corbyn either implicitly or explicitly repudiates.

Despite those who now claim him, Attlee was no dogmatist or revolutionary, saying of why he joined Labour, “It was inclusive rather than exclusive, and it preached a socialism which owed far more to the Bible than Karl Marx…a characteristically British interpretation of socialism, a way of life rather than an economic dogma.”

If Attlee’s government serves as a model Labour one, it is not as a paragon of pure socialism but as a the pinnacle of post-war co-operation both within and outside the Labour movement. The architects of its major social programs and economic policy were both Liberals — Beveridge and Keynes. It was accepted by all parties (and the Americans) that a massive reconstruction effort in Britain and Europe was required, and that a population which had seen the country through its darkest hour should not be left in any more hardship than was absolutely necessary. Within Labour, the party’s patriotic and security conscious tradition had understandably triumphed over its pacifist one while its pragmatists and idealists both shared a belief in means as well as ends in the creation of the welfare state (once created of course, disagreements over its application and aims were and are plentiful).

Going further back, the motion founding the Labour Party, as the Labour Representation Committee in 1900, proposed by one Keir Hardie, read, “a distinct Labour group in Parliament, who shall have their own whips, and agree upon their policy, which must embrace a readiness to cooperate with any party which for the time being may be engaged in promoting legislation in the direct interests of labour.”

The party itself was founded not just by the pure, but from a variety of traditions including liberals, Fabians, trade unionists of all stripes and ordinary working men (and at that point, it was overwhelmingly men) who shared the aims of improving conditions for Britain’s poorest. Hardie himself helped defeat a motion recommending an early forerunner of the party be called ‘Socialist Labour’ — precisely because it would limit the fledgling movement’s appeal.

The point of this abridged overview of Labour’s history is not to claim that New Labour was a perfect inheritor of Attlee and Hardie’s principles — but that it was well within the party’s pluralistic and practical tradition. That it was not an abandonment of Labour values but a leader and his colleagues’ application of them in a modern context. This is not to argue that they were completely right, or that a similar approach is needed now, after all, few would disagree that New Labour made major mistakes. There were blindspots, compromises too far, Iraq, and clearly after Gordon Brown was rejected by the electorate a new approach was needed, one which Ed Miliband failed to provide.

But there’s a huge difference between arguing for policy changes and defining your party’s pragmatists as heretics to its tradition. Corbynism doesn’t just do this — it is its animating force, its reason for being. It is why Corbyn refuses to resign when told by 80% of his MPs they do not think he is up to the job. It is why he has as his policy chief a man who last year openly celebrated Ed Balls losing his seat. It is why the term ’Blairite’ and ‘Red Tory’ have been thrown at anyone who dared question the new boss’s wisdom, even when it is against official party policy. It is why MPs who actively disagreed with Tony Blair, or who as late as last year were championed by prominent Corbyn backers like Owen Jones, are subject to abuse after saying they find it impossible to work with the leader and his staff. It is why when they recount the experience of working for Jeremy in terms such as, “I hated being part of something so inept, so unprofessional, so shoddy. There was no effort to build a team. Good people recruited to his office soon left,” their criticisms are not taken in good faith, as those of the people who are the Labour Party’s greatest servants, but are seen as evidence of a ‘right-wing’ conspiracy.

And let’s be clear what the implications of this view are. That anyone, from left-wing economic thinkers, to long serving MPs, and most importantly of all, voters, who doubt the leader’s program or ability to deliver it are unwanted, corrupt or not real Labour supporters.

To those backing Corbyn,it is not a rational choice about who is best to lead the party, but an emotional declaration of yearning for a pure, traditional socialist party over a ‘Tory lite’ one. The problem is Labour has never been the party they want to restore it to being, nor was it ever the one they thought it had become.

The myth of abandonment didn’t begin with Tony Blair, it didn’t even begin with compromises brought on by the turmoil of the 1970s, or necessary hardships of the 1940s — it began with the creation of the Labour Party itself. It began then because the very thing the Labour Party was created to be , a big tent party of the parliamentary left, was designed to disappoint socialists demanding dedication to dogma rather than coalition building.

For most parts of the party’s history the myth has been confined to the fringes of Labour, incubated in the alphabet soup of Socialist and Workers’ Alliances baying for the revolution, protest movements and the few Labour MPs who make common cause with them. The last time it erupted into its mainstream, during Militant’s peak in the 1980s, the party was out of power for 18 years. Even then, despite the best efforts of one Jeremy Corbyn, its proponents were beaten back from the top of the party. Now, it is the leader’s very reason to be, and seemingly a majority view among the membership. If it remains so, the Labour Party will die as a major political force and will probably deserve to.

That is no exaggeration — much of the criticism of the Labour leadership has understandably focused on electability and competence, but these are secondary indicators of a more fundamental point. To the centre-left, security conscious part of Labour’s historic electoral coalition, Corbyn is not the wrong leader because he is unelectable, but is unelectable because he is morally indefensible. As for why he and his team are incompetent, it is because he values ideological adherence above expertise and ability.

At this point, Corbyn’s supporters are entitled to ask why this is so? Why is it no different to say, Tony Blair’s differences with the left of the party? One could state that, although Labour leaders from Kinnock to Miliband faced threats of challenge and constant rebellion from Corbyn and McDonnell, they never set up or made common cause with organisations calling for their unwavering support or else purging from the party. One could list his long history of associations with deeply unpleasant hard left figures and organisations, who’ve long called people on the centre-left “scum” or ”traitors”, who’ve indulged anti-Semites when it’s suited their cause. There’s his documented support of the IRA (and opposition to the Good Friday agreement) and repudiation of Nato. There’s Corbyn’s interactions with those who dare question him, and the bizarre denial of inconvenient truths and the lies and casting of aspersions designed to cover them up or deny them.

An avowed Trotskyist is on the steering committee of Momentum, yet Trotskyists are apparently non-existent among Jeremy’s support. Anti-semitism isn’t a problem among a section of his support — yet a leading Momentum campaigner abuses a Jewish MP at the launch of a report into the subject. He says abuse hasn’t increased within the Labour Party — but 40 female MPs say otherwise, he has received 96 pages of testimony from one MP on the subject and a glance at the Twitter mentions of any of those MPs who refuse to back him would reveal this to be either a delusion or a lie. Corbyn has had the worst ratings of any opposition leader and Labour has been behind in almost every single poll, pretty much since the day he became leader — and yet he and his backers deny this reality and blame it on others.

But it’s not these things in isolation that are the problem, it is the attitude which underlies them. That those who are on the right side, who have accepted the one true religion are always right and honourable. There is always a theory or an explanation for why their beliefs don’t match up to the facts or rhetoric to actions. Conversely, those who point out faults or express misgivings, must be motivated by something other than their own belief in Labour values.

By its very nature, Corbyn’s is a worldview which divides the world into true believers and enemies to the cause (and those they mislead). It always has done, and it always will do — otherwise, what is the point? Why not believe his colleagues when they say he’s not up to the job? Why not take polls that declare the leader a disaster at face value or listen to the advisers who’ve said he took up their ideas but singularly failed to turn them into something coherent? Why claim winning 280 votes in a parish council by-election as a victory the media didn’t report? Why not resign as the leader of a parliamentary party when 172 of its 230 MPs, say they have no confidence in you, and not resigning will instigate a civil war threatening the party’s existence? Why not say, “I’m disappointed and I know my supporters will be but it is clear I would be unable to form a Labour government,the first duty of a leader, and therefore for the good of the party I must resign. I know however my support among the membership still exists, and I will be lobbying for their policies at conference and beyond,”?

For that matter, why claim a government that halved child poverty and introduced many of the measures you’re horrified are now being abandoned as alien to the party’s tradition?

Instead Corbyn took to his fire truck, and signalled that this was not about uniting the Labour Party but purging it and warping it to his specific vision — a movement that Labour has never been in its history with very good reason — it wouldn’t have been able to reach out, make common cause with others and gain mass parliamentary representation, let alone implement its many achievements. Worse, with its tenuous grip on reality, it wouldn’t have had the intellectual capacity to.

Of course Jeremy Corbyn’s leadership did not occur in a vacuum, or rather it did. The failure of the soft left and right to offer a renewed vision of what it means to be a successful centre-left party kept the the door open for Corbyn’s poisonous account of Labour history to take hold. A younger generation (to which your writer belongs), who are among his least ideologically fervent backers, but biggest in number, banked New Labour’s successes (until they began to be undermined by the Tories and demanded full-throated opposition at any cost) but were scarred by its failures. As a result they understandably yearned for a return to high principle, and were attracted to a man who in contrast to his uninspiring opponents, appeared to offer it in gloriously simple terms. Many of them do just want a party that is less technocratic and more in tune with their concerns — but it is not what they will get.

Because Jeremy Corbyn isn’t a return to the values of the Labour Party — he is the manifestation of the toxic myth that is killing it, because for members who do not agree with his narrow, and distorted vision of Labour history, and more importantly millions of voters who do not, it no longer feels like home, and they do not feel “welcome”.