It’s hard to imagine what Friedrich Engels would make of John McDonnell’s frugal dining habits. Engels, co-founder of Marxism, spent his 70th birthday sharing 16 bottles of Champagne and “12 dozen oysters” — and boasted of his “acknowledged gift for mixing a lobster salad”.

By contrast, McDonnell — perhaps the most famous living Marxist in Britain — is strikingly abstemious. When I ask where he normally eats in Westminster, the shadow chancellor replies: “I don’t really. Not usually.” For lunch today he ate some Rich Tea biscuits.

It is 4pm and we are meeting for a ludicrously early dinner at a café in his constituency of Hayes and Harlington, a gritty multicultural suburb of west London. The veteran socialist usually eschews all corporate hospitality; he has made an exception for Lunch with the FT, but it’s not going to be haute cuisine.

McDonnell is one of the most intriguing figures in British politics, a man who will wield huge influence if the opposition Labour party somehow takes power as a result of the Brexit chaos. The current Labour leadership is the most left-wing in its century-long history. “People want change,” he says. “Change is coming; as simple as that.”

As party leader Jeremy Corbyn’s closest ally, the shadow chancellor has spent decades in the political wilderness. Over the years he has suggested that Tory MP Esther McVey should be lynched, urged workers to spit in their managers’ tea, and said IRA terrorists such as Bobby Sands should be “honoured” because their “bombs and bullets and sacrifice” led to peace in Northern Ireland.

Yet in the upside-down world of British politics he has emerged as one of the more consensual “Corbynistas”. He has tried to bridge the divide between Corbyn and his hostile MPs and spends much of his time trying to convince business leaders that they should not be terrified of a Labour government.

And then there is Brexit. Labour has been suffering in the polls from trying to appeal to both Leavers and Remainers just as Britain’s Brexit debate becomes increasingly polarised. McDonnell is one of the most senior figures to have tried to force Corbyn away from his fence-sitting, pushing for a more pro-EU position. In the weeks since our meeting, the party has become engaged in a bitter tussle to prevent Boris Johnson from carrying out a no-deal departure from the EU.

McDonnell has cultivated a more reasonable persona. He credits the makeover to his parish priest, who told him: ‘Soften your image’

I arrive at his constituency office just off Hayes high street and am shown into his study. McDonnell is writing letters, sleeves rolled up. The “hard man of the left” has a strikingly weak handshake.

We head out to eat. McDonnell lives in one of the poorest wards in Hayes. We walk past Pound & More, a discount shop, the Ali Halal Meat butchers and fried chicken outlets, before coming to a halt outside Nandini’s, a thali café. It’s a cheerful little place with bright orange sweetmeats and bottles of “Thums Up” soda in the window, and counters full of Indian desserts.

We’ve agreed in advance to have curry and beer, so McDonnell suggests the “thali of the day”. But when he asks for beer, the manager points to a fridge stocked only with cans of soft drink: it’s going to be a sober gathering after all.

Parish priest makeover

Back in 2015, when Corbyn gave him the treasury role, McDonnell was seen as the thuggish sidekick to his beatific leader. Since then, however, McDonnell has cultivated a more reasonable persona. He credits the makeover to his parish priest, who told him: “Soften your image”.

Today he is dressed in the sober dark suit, white shirt and red tie that he wears to business events. Some of the executives he meets are wary or even hostile, but others offer him a respectful hearing. Either they are un­familiar with his anti-capitalist history, they like his serious demeanour, or — most likely — they are fed up with the current Conservative government and its approach to Brexit. “We’ve got business leaders coming to us looking for stability, which they’re not getting from the Tories,” says McDonnell. “It’s enhanced our relationship in that sense.”

Not with everyone, though. There are many who fear that a Corbyn-led government would represent a whole new level of instability, with nationalisations and a ramping-up of tax and spending. McDonnell makes no pretence otherwise, arguing that his reform programme is more ambitious than that of Labour prime minister Clement Attlee, who set up the welfare state some 70 years ago: “We all admire what Attlee did ... but I think we will go beyond it.”

I start with a bit of musical small-talk. The Liverpool-born MP is a Beatles fan, and tells me that not seeing the band live is his “biggest regret”. But McDonnell has serious classical tastes too, mentioning Shostakovich’s ninth symphony as a particular favourite. I ask if he enjoyed The Noise of Time, Julian Barnes’s novel about the Russian composer.

“As an insight into Stalinist society, it’s really interesting; he was a remarkable character ... he survived, which was a miracle. When Stalin criticised his symphony and it never got played again, he did what people thought was a grovelling apology but it wasn’t, the message was, ‘I’ll see you out, no matter what you throw at me I’m going to keep going’.”

I ask how he would explain the difference between “Marxist” and “Stalinist” to a typical FT reader. “Take a Christian,” he says carefully. “You read the New Testament and you think there are fundamental truths in it. But you wouldn’t blame Jesus Christ for the Spanish Inquisition. I think it’s the same analogy. If Marx was alive during the Stalinist period, he’d be first to be in the gulag.”

I point out that there are countless examples of functioning Christian countries: it’s harder to make a list of successful communist states. McDonnell appears to concede the point, but argues that Marx’s ideas have fed into successful socialist governments. “Attlee’s socialist practice came from that understanding of capitalist analysis by Marx himself.”

The manager sets down matching tin trays, each with rice and half a dozen dishes — including chickpea curry, yoghurt and cauliflower and potato — with a spicy poppadom and chapattis. We tuck in.

For decades, Labour’s small clutch of hard-left MPs, known as the “Campaign Group”, were pariahs within the party. Among them, McDonnell was the serious one, responsible for finance at the Greater London Council during the “loony left” 1980s.

Peter Mandelson, co-architect of New Labour, promised to banish McDonnell and his comrades to a “sealed tomb”. The tomb broke asunder with the arrival of Corbyn as Labour leader in 2015, smashing decades of centrist consensus. “I’ve always said the left needs to be ready for government,” says McDonnell. “‘Be ready tomorrow, because things can happen.’ That time has come.”

McDonnell says he will ban bonuses in the City of London unless the financial services industry takes action to curb excessive payments

McDonnell wants to shift power and money from landlords and bosses to tenants and workers, and he makes no apologies for this. “[The plan] is trying to rebalance the power between capital and labour.” His vision is of an intervent­ionist government seeking to eradicate homelessness and low pay and tackling the housing crisis. For executives, the picture is not so rosy: they face public pay transparency, higher taxes on salaries and an end to share options and golden handshakes.

McDonnell says he will ban bonuses in the City of London unless the financial services industry takes action to curb excessive payments. “If it hasn’t learnt its lesson, we will take action, I’ll give them that warning now,” he says, spearing a square of paneer with a fork. “People are so offended by it. It’s a reflection of the grotesque levels of inequality that people now find so offensive. Action will be taken, full stop.”

I point out that the Square Mile is part of an international industry and that — like his beloved Liverpool FC — employers need to offer high wages to attract talent. What would he say to Rich Ricci, former CEO of Barclays Capital, who was paid £44m in one year alone? “I’d point him towards Julian Richer,” McDonnell replies, without missing a beat, referring to the hi-fi entrepreneur who has recently given his staff a big chunk of his company.

Many of McDonnell’s ideas would have been considered political suicide only five years ago. But Labour’s gains in the snap 2017 general election have forced many critics to rethink that view. Labour was ahead in opinion polls in the early summer, although Boris Johnson has since opened up a 10-point lead: for now.

Fear of Donald Trump

McDonnell says he is inspired by the writings of Antonio Gramsci, an Italian communist of the inter-war years. “What Gramsci is all about is hegemony: you win the battle of ideas and it dominates,” he says, emphasising his point with a raised fist that he moves from side to side.

While many Labour MPs still resent Corbyn’s leadership and are angry about his failure to close down a long-running row about anti-Semitism in the party, most have accepted the need for radical economic change. “I think ideologically the Labour party has moved on dramatically ... no MP kicked off about the last manifesto, we had no complaints. There might be criticism of Jeremy and myself ... but we’ve hegemonised the debate in the party around policy.”

The shadow chancellor’s world view has become more mainstream in recent years, but so too has the nativist populism of the right. McDonnell says he does “fear” Donald Trump, and is anxious about the potential for trade disputes and misplaced foreign interventions. Yet he believes that his own movement can surf the anti-Trump backlash.

“The reaction to Trump has been remarkable: we’ve now got a debate for the first time in maybe a generation or two generations in America about the nature of socialism. The reaction to Trump is a blossoming of the labour and trade union movement over there.” He will visit the US in the autumn and hopes to see Democrat left-wingers such as Alexandria Ocasio-Cortez and Bernie Sanders.

The Tories have tried to portray the McDonnell manifesto as a template for a “return to the 1970s” or — worse — the transmutation of Britain into a latter-day East Germany. The Institute for Fiscal Studies (IFS) think-tank said the 2017 manifesto would take taxes to their highest-ever peacetime level. Yet some left-wingers, even a few who sit alongside him in the shadow cabinet, think he is too cautious and pragmatic.

While Labour’s tax changes may sound radical, the centrepiece tax rise — a corporation tax hike — leaves the levy at a lower rate than in 2010. Unlike the previous Labour leadership, Corbyn and McDonnell have resisted the idea of a “mansion tax”, worried that it will hit many public-sector urban voters. He admits: “It’s what’s achievable in terms of keeping people with us and bringing people with us ... what we don’t want to be in is a situation where we undermine the support we need to get into government.”

A decade ago he wanted higher aviation taxes. Now he says ‘it’s not on the agenda’. Back then he wanted to nationalise BP as punishment for its high profits

We talk in detail about McDonnell’s more blue-sky ideas, as bhangra music blares in the background. He is mulling a much tougher “zero-carbon” target — under pressure from activists — and wants to explore a “buy-to-let” for private tenants as well as a blanket ban on City bonuses. “I want a government that intervenes and that is going to intervene on a large scale.” 

This is the tub-thumping radical familiar to anyone who has paid attention to the Corbyn movement. Before getting the train west, I went through some of McDonnell’s “early-day motions” — a kind of parliamentary petition — from when he was an obscure backbench MP. A decade ago he wanted higher aviation taxes. Now he says “it’s not on the agenda”. Back then he wanted to nationalise BP as punishment for its high profits, according to one motion I found. Now he says something vague about being “committed to a just transition”: “We’re not nationalising them.”

Corbyn once talked about a pay cap on all executives: now there is a more symbolic plan for a 20:1 ratio threshold between bosses and staff — but only for companies with government contracts. In the spring, McDonnell threatened to de-list companies that did not meet strict environmental criteria. Now he plays that down: “I think rather than de-list there’s other mechanisms we can look out for how to tackle it.” 

McDonnell takes a handful of chapatti and starts scooping up some lentils, mopping up the juice. Would he be a pragmatist if Labour gets into power? He has commissioned a swathe of reviews that sound radical but will not necessarily translate into hard action. One of those is into a four-day week, but his vision is more one of flexible hours than a three-day weekend. “For some people a four-day week is ridiculous because they’re desperate to get the hours just to survive at the moment, but there’s another group of people working all the hours God sends and it impacts on their family lives.”

Corbyn’s views on foreign policy have been another source of controversy for the Labour leader: anti-Nato, anti-Israel and — in the past — sympathetic to hard-left regimes such as Venezuela and communist Cuba. McDonnell is rarely asked about those issues, but he says there isn’t a cigarette paper between the two men on foreign policy. While Labour policy is to support Nato, he is critical of “sometimes its aggressive nature”.

By now we are eating the pudding, a small, sickly sweet brown ball. I throw him the question that has made other politicians stumble: “What’s the naughtiest thing you’ve ever done?”

My mind flickers back to McDonnell’s study, where there is still a tribute to IRA terrorists. He looks me in the eye: “I’m not going to admit to it because I could still be arrested.”

There’s a pause. “I presume you’re joking?” I reply uncertainly. He leans forward and produces a stony death stare, before relaxing his face: “Of course I am.”

As we leave, McDonnell puts a couple of coins into the tip box. Out on the drizzly pavement, I ask about the longevity of Corbyn and McDonnell.

He predicts his old friend will still be leader after a hypothetical five-year Labour term, despite persistent rumours of Corbyn’s health problems. “That’s for him to decide but I can’t see any reason why not, he’s perfectly fit, stamina of a young man,” he says approvingly of his 70-year-old friend.

McDonnell is three years younger but had a heart attack six years ago. “You realise that you’re not immortal,” he says. “You seize the moment, carpe diem.”

© The Financial Times Limited 2019