There is an unspoken rule among Scottish writers that we don't slag each other off in public. The rule runs thus: coming, as we do, from a small, colonised nation, we automatically find ourselves marginalised by literary London and must fight doubly hard to gain the recognition abroad that is granted to English writers. While we may express private reservations about the work of another writer, we don't scupper their chances by saying this publicly. After all, each of us takes enough of that from critics.

That changed over the weekend. Speaking at the Edinburgh International Book Festival, Scotland's only Man Booker prize winner, James Kelman, lambasted his country's literary establishment for praising the "mediocrity" of "writers of detective fiction or books about some upper middle-class young magician or some crap". Attention paid to the twin commercial giants of (presumably) Ian Rankin and JK Rowling had served, Kelman argued, to obscure Scotland's more radical tradition.

This has split the nation's literature in two. In a debate in the Sunday Herald headed 'Is Pulp Fiction Taking Over Scotland's Bookshelves?' daggers were drawn over the crime-ification of Scottish letters. The novelist Rodge Glass said that Kelman had been "very brave" in his remarks, while playwright John Byrne, spoke of "the danger of Scotland becoming known as the home of genre fiction, a factory churning out these things". And the response was ferocious. Professor Michael Schmidt of the University of Glasgow, defended the common reader against Kelman's "Stalinist" and "parochial" approach. Crime writer, Denise Mina, derided "this awful schtick about pushing the boundaries of literary technique", comparing it to "asking people to appreciate the welding on their plumbing".

As a manifestation of the old 'genre v real literature' chestnut, the debate should be just as interesting to those outside of Scotland. Kelman, committed to experimental form and language, sees genre fiction as redundant, compromised by commerciality. Mina, while still calling Kelman a "beautiful writer", regards his stance as a mere "play for status"; a failure of the writer's duty to entertain.

There is another to level to this, however, about the ways in which any country's indigenous literature – especially those of smaller or post-colonial nations – is threatened by the commercial imperative to produce page-turning, airport-friendly thrillers. A third level concerns the collusion of the literary establishment in this. It's certainly the case that the books editors of broadsheet newspapers will bemoan the fact that we're not all reading Tolstoy, while providing acres of coverage to crime writers. Genre fiction doesn't need highbrow attention in order to sell by the bucketload, yet editors must cover it precisely because it is so visible. This crowds out more risk-taking writers, for whom a single review from a perceptive critic can provide a career breakthrough.

It is galling, then, that a country like Scotland, home to an enormous, bristling, experimental tradition which includes James Hogg, Alexander Trocchi, Hugh McDiarmid, Muriel Spark, Edwin Morgan, Tom Leonard, Alasdair Gray, Janice Galloway, Irvine Welsh, Alan Warner, Ali Smith, James Robertson and Kelman himself, is marketed to tourists as the home of Rebus and Potter.

One doesn't want to decry authors who are certainly outstanding in their field (constructing a page-turner requires narrative skill); neither does one want to sneer at the tastes of book-buyers, for whom reading at all in this age of distraction is an increasingly fought-for pleasure. And it's not as though writers such as Mina, Val McDermid or Christopher Brookmyre aren't working a left-wing agenda into their books; they are. But genre fiction is, by definition, generic. Mina's disdain, in her comments, for pushing boundaries of form is palpable. The genre writer's first responsibility is to the genre itself: they must fulfil readers' expectations for convention, or they have failed. It's easy to see how this becomes part of a capitalist enterprise, which requires market 'product' and fears innovation as a 'risky sell'. At a time when capitalism is scouring livelihoods, however, we must empower writers such as Kelman to speak out against it, and put forth new ways of expressing and thinking about ourselves. This is far from being just a Scottish issue.