In 1979, Labour prime minister James Callaghan remarked on the eve of a doomed general election: “There are times, perhaps every 30 years, that there is a sea change in politics. I suspect that there is now such a sea change – and it is for Mrs Thatcher.”

Two years later, with a recession biting and riots brewing, about 300 unemployed men and women marched from Liverpool to London under the banner of the People’s March for Jobs. One of the three key organisers was Pete Carter. A bricklayer from the West Midlands, he stood as the Communist candidate in Wolverhampton in the 1970 general election, against Enoch Powell; he played a role in the 1984-85 miners’ strike, and became the industrial organiser of the Communist Party of Great Britain. After his death in 2011, an obituarist described him as “the greatest working-class orator I have ever seen”.

Mike Carter, a Guardian journalist, is Pete’s son. As a child, he idolised him, but that changed. He grew to hate this self-pitying firebrand of a father; later, after Pete walked out on the family, Mike blamed his desertion for the cancer that killed his mother. In 2011, in their final encounter, Mike “reeled off grievance after grievance, the anger and hurt he had caused to me, my mum and [sister] Sue”. Pete replied: “I sacrificed everything for the struggle… You don’t understand.”

“The fucking struggle,” Mike said, “it’s all we ever heard. Look around you. It’s all fucked. Your life’s work. Was it worth it?”

A fortnight later, riddled with lung cancer, Pete died on his narrowboat, after he fell and hit his head. “By the time I got there from London,” Carter writes, “the body was gone.”

On 2 May 2016, Carter set out to retrace the route taken by Pete and the People’s March for Jobs 35 years earlier. If the political landscape seemed familiar, his father’s footsteps were not. All Together Now? is a quest to take the pulse of a nation after six years of austerity, and to plot a familial reconciliation.

Carter is the author of two successful travel books; the first inspired by a midlife crisis, the second a farewell bike ride around a Britain so inspiring he found it, ultimately, impossible to leave. Here, he is at ease traversing 330 miles across the heart of England in four weeks – every inch by foot – savouring everything from the salt marshes of the Mersey to the faded grandeur of our post-industrial cities. There are astute reflections on the borders of our accents; our fight-or-flight impulse; how the price of a pint of beer rises a penny a mile heading south, and on our “desire paths”, the illicit trails we carve into the landscape in defiance of ordained boundaries. His struggle to locate Pete – both internally and within the landscape – reveals a vulnerability that will resonate with many who have lost a parent they never really had.

From Liverpool to Widnes, Salford, Macclesfield, Birmingham, Northampton, Luton, and on to the capital, Carter is hosted by original marchers (some still cradling commemorative mugs), and by those fighting the good fight today – social workers, teachers, labourers, council workers and church volunteers.

The bigger picture is bleak: All Together Now? maps a country in crisis. It is a searing critique of how 40 years of neoliberalism has ruined the lives of ordinary people. In health, jobs, housing, transport, our public spaces, welfare state and sport, the working class, Carter finds, have been disenfranchised or priced out to such an extent that England has suffered a moral, financial and spiritual collapse.

In Salford, while buy-to-let investors “up from the south for the day” snap up entire streets for their portfolios, Victorian illnesses have resurfaced, in the form of rickets and beriberi. In Northampton, Birmingham and Stafford, the homeless and mentally ill are clustered in churches and doorways. With Tory cuts wrecking council budgets, Sonia, who works at a drop-in centre for the over-50s in Bedford, has to plead for grants from private trusts. “We do everything but sell our bodies,” she says.

In Stockport, the Hat Works museum is pretty much all that remains of an industry that sustained the town from the 19th century to the 1990s. There are similar fragments in the Potteries, where 50,000 jobs have disappeared since the 1970s. In Stoke, on the eve of the 2016 EU referendum, the chief executive of the YMCA warns: “People are waiting to be rescued.” But he knows they need to be empowered, not bailed out; that Vote Leave was decades in the making – a rejection of a top-down approach that failed to deliver a trickle-down windfall. In Nuneaton, a retired factory foreman tells Carter: “If the economy goes down the toilet, at least those bastards [in London] will finally know what it feels like to be us.”

Carter is a lovely writer, with an engaging, lyrical style; his tone is sympathetic but rarely sentimental, and the chapters are evenly spaced out along the route. There are no countervailing voices, however, and we occasionally lose sight of the landscape, and Pete too, as he embarks on a lengthy disquisition about the ravages of the free market.

Ultimately, he finds the London he returns home to “a simulacrum of a city, really, a soulless plutocrat’s Potemkin village”. As Mike enters Trafalgar Square, there is a tentative sense that his desire path has brought him a step closer to his father. I wish he had gone a little further – half a mile down Whitehall. Because this important, disturbing and frequently heartbreaking book should be read by every politician in Westminster. The English patient is on the brink.

Adrian Tempany’s And the Sun Shines Now: How Hillsborough and the Premier League Changed Britain was shortlisted for the Orwell prize.

• All Together Now? One Man’s Walk in Search of His Father and a Lost England by Mike Carter is published by Guardian Faber (£14.99). To order a copy for £9.99 go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99