Herbert Morrison, the deputy prime minister throughout the Attlee government, was both the literal and ideological grandfather of New Labour. Peter Mandelson, the faction’s third man alongside Tony Blair and Gordon Brown, is his grandson – and ideologically, Morrison was a centre-left politician from the party’s social democratic wing.

He was also the author of one of our most misunderstood quotations: “Socialism is what a Labour government does.” He wasn’t claiming socialism as the mission statement of the administration, but rather arguing that anything which broadly met Labour’s aims could be seen as socialism.

If Jeremy Corbyn were to quote Morrison, most observers would assume he had the first meaning in mind. But the Labour leader is becoming better versed in another echo of New Labour: triangulation. Over the last two years, he has proved surprisingly adept at compromise on issues outside his core values. We are beginning to see where he is willing to give ground – and which dissenters can gain his attention.

In last year’s election, Corbyn – once a strong critic of overreach by the police –made opposing cuts to the force a centrepiece of his argument against austerity. His manifesto retained the cap on welfare benefits and pledged an end to the free movement of people. John McDonnell, the shadow chancellor, has committed to matching the Conservatives’ tax cuts for those earning between £55,000 and £70,000.

Like beloved rock stars, McDonnell, Corbyn and shadow home secretary Diane Abbott use their old hits to mollify the crowd whenever the experimental stuff starts to turn people off. No one can reasonably claim that Abbott – with her long history of campaigning for civil liberties and her support for victims of police violence – lacks a critique of the carceral state. It’s just that her critique was nowhere to be found in the 2017 Labour manifesto – and it won’t be in the next one, either. She, too, is willing to be accommodating. It is in the Cabinet Office brief of the fourth member of Labour’s ruling quartet, Jon Trickett, that Corbynism is at its most unrestrained and radical. The Cabinet Office’s role is vital to the guiding belief of the domestic Corbyn project, which is that the state should have a more active role in commissioning and delivering services. This ambition goes well beyond infrastructure projects and into areas as diverse as the running of prisons and the recycling of water.

In the real world, the exemplar of that approach is Preston City Council, which is frequently cited by McDonnell’s aides, and is in many ways the first “Corbynite” council. Under the “Preston model”, local authorities are encouraged to award contracts to small, local suppliers rather than international conglomerates or outsourcing giants. (Preston increased the share of its budget spent locally from 14 per cent in 2012 to 28 per cent in 2016.) Labour’s “Big Four” all subscribe to this agenda, and their commitment to it has only been strengthened by the collapse of the private contractor Carillion. Tougher controls on such companies, a proposal unveiled by Trickett this week, are the result of months of discussion in the leader’s office.

Corbyn’s team feel that reforming the relationship between the state and private sectors is an area in which they must be radical. As one puts it, the shift is between Whitehall as a “customer” and as an active participant, owning and providing services which have, for the past four decades, largely been outsourced to the private sector. If voters want a few extra quid for the police and relative timidity on rates of tax in return, that feels like a fair exchange.

Not all Corbynite MPs (or supportive outsiders) share that view. So far, though, fear of a counter-revolution is strong enough to restrict disquiet to the odd raised eyebrow or barbed remark at the expense of the shadow treasury team.

This means the subject of internal Labour dissent which gets most airtime is Europe, with articulate pro-Remain MPs from the party’s right regularly appearing on television in the hope of nudging their leader’s position towards continued membership of the customs union, if not the single market.

Fairly or unfairly, however, dissent from the likes of former shadow chancellor Chris Leslie or former shadow business secretary Chuka Umunna doesn’t register in the leader’s office. If anything, it further entrenches the Corbynite scepticism of the whole European project.

The place where dissent can – and does – influence the leadership is the Monday afternoon meeting in the Norman Shaw Buildings at Westminster. Corbyn, McDonnell, Abbott and Trickett, along with their senior staff, meet to discuss strategy and the wider direction of the party. This meeting sets the tone for the others later in the week, including the shadow cabinet.

Corbyn’s passion is foreign affairs: during the years of New Labour hegemony, staffers in McDonnell’s office used to refer to him as “the left’s foreign secretary”. And so he is happy to defer to his allies on domestic policy. But Brexit straddles that divide, and Labour’s core team is split three to one. Only Abbott is particularly fond of the European project, while the rest of the ruling quartet are sceptical about the role of the European Court of Justice and its history of what they see as neoliberal judgements.

Leaving the jurisdiction of the ECJ means accepting what most observers would describe as a “hard Brexit” – in just the same way as ending freedom of movement does. So far, that is a trade-off which the broader movement is willing to accept in exchange for Corbyn’s left-wing programme. This accord ought to hold for the rest of the parliament, provided, of course, that it looks like winning is something Corbyn can do.