The early weeks of 2017 were traumatic for Alex Niven. His newborn son was not sleeping. His partner had suffered significant blood loss during a difficult birth. Then his friend Mark Fisher, the founder of the K-Punk blog and the “intellectual leader of a generation” as Niven describes him, killed himself. All this coincided with a period in which Corbynism seemed to be in retreat. Niven could scarcely sleep and, as he writes in his latest book, New Model Island, he began listening obsessively to Echo & the Bunnymen’s “The Killing Moon”. “It felt like a completely hopeless moment,” he told me. “A moment of total disillusionment and defeat.”

He writes about this disillusionment and how it eventually lifted in New Model Island, which mixes theoretical analysis about our disunited kingdom, polemic, memoir and cultural criticism and is influenced by the writings of Fisher. When we met recently at the New Statesman offices in London, I asked Niven about his friend’s legacy.

Fisher (pictured above) was 48 when he died and had spent much of his career feeling marginalised, as a writer and academic. “Mark was a kind of precarious labourer on the fringes of academia,” Niven told me. “He was marginalised in a very literal sense because apart from a year or two before he died he only ever had temporary fellowships in further education.”

Fisher’s experiences resonated for a generation of millennial students who were highly educated but did not have job security and could not afford a home of their own. “That, in a sentence,” says Niven, “is the basis of intellectual Corbynism. Corbynism is not really about Corbyn: it’s about this intellectual generation that was waiting for its moment to cross over and hadn’t been able to because of a precarious work culture.”

What Niven calls the “neoliberalisation of education” affected Fisher. He channelled his frustration into writing Capitalist Realism (2009), which explores, as Fisher wrote, “the widespread sense that not only is capitalism the only viable political and economic system, but also that it is now impossible even to imagine a coherent alternative to it”.

Niven admires what he calls the “almost spiritual dimension to Mark’s writing. Capitalist Realism is about how we are spiritually impoverished. We are trapped psychologically in this punitive, almost dystopian, work culture.”

One consequence is people’s feelings of powerlessness. Another is their inability to conceptualise a future that is different from the present. “The feeling that we can’t express alternative ways of being and ways of thinking – for me that’s the main thing Capitalist Realism does well by personalising the effects of neoliberalism.”

Niven is a lecturer in English literature at Newcastle University and he’s also worked as an editor on the imprint Zer0 Books, which was founded by the novelist Tariq Goddard and published Fisher. His latest project is editing the letters of the modernist poet Basil Bunting for Oxford University Press, but as an academic he faces a conundrum. “This is the book I want to write” – he points to a copy of New Model Island – “and it says all the things I want to say but I will struggle to get it on to the REF [the Research Excellence Framework] because it’s not an academic monograph. We have reduced academic labour to quantitative measurements, to tables and targets. Capitalist Realism, which wasn’t on a university press imprint, was marked low on the REF.”

This is regrettable. New Model Island can be dense in places. The language is often technical, in the style of academic cultural studies. But there are passages of arresting memoir, it makes a powerful political argument directly relevant to the constitutional moment, and it looks beyond the (inevitable?) break-up of the United Kingdom through advocating a new kind of “radical regionalism”. Above all else, it makes you think.

In person Niven, bespectacled and lightly bearded, is unassuming, even bashful. He speaks quietly and slowly and, for a polemicist, is not at all combative. Like Fisher – like me! – he became a reader because of the music press, particularly the NME.

“I was growing up in rural Northumberland and read the NME every week and it was a source of education. But around 2001, after having sections on dance music and politicised letters pages, it suddenly became very mainstream.”

The response of Fisher and others to the decline of the NME and the conservatism of the mainstream media was to start blogs and open up their own creative spaces. This, the architectural critic Owen Hatherley wrote of his friend Fisher after his death, was “writing of a sort that wasn’t supposed to exist any more”.

Or, as Niven puts it now: “The music press had sold out and we were the music press in exile.”

One of the ideas in Niven’s book is that Englishness is “defined by absence or hiddenness”. He struggles “to see a coherent basis for England and Englishness” and is sceptical of what he calls a unitary patriotism. “The only time I’ve really felt English is watching the England football team. We don’t exist as a national culture because we were an imperialist internationalist culture.”

The ultimate purpose of the book “was to try to imagine something beyond both Englishness and Britishness if that were possible”. He’s on to something – because creating a new national imaginary will surely be the defining challenge of the age of Brexit.