If you want to understand the populist media’s underlying agenda then you have to look not only at what gets published, but what doesn’t.

Remember the great peril that threatened to bring Britain to its knees, consigning our history and culture to the dustbin of history? What, you’ve forgotten already?

I’m talking about immigration. It was the press phenomenon of the age 10 years ago, and for at least the following six years – right up to the EU referendum. Since then, however, immigration has all but disappeared from newspaper pages.

References to migrants, asylum seekers and refugees have almost vanished along with the associated prejudicial buzzwords and phrases, such as swamping, influx, surge, illegal, bogus, sham, jungle, welfare scroungers, benefit tourists.

Remember those dehumanising, derogatory metaphors such as parasites, leeches and cockroaches? Gone … at least for the moment.

We were told the UK was full up and there was no room for anyone else. Images of the world’s poor on the verge of “invading” Britain were painted in numerous articles. Immigration was, supposedly, a crisis of unimaginable proportions.

The daily newspaper diet of large anti-migrant headlines, accompanied by xenophobic columnists retailing thinly veiled racist rhetoric, was so common it became a cliché for us critics to complain about it. Yet as much as we railed against it, editors redoubled their efforts, ignoring rational arguments that exposed their distorted agenda.

Britain was not alone in dealing with the arrival of migrants and refugees. It was happening in every European country, but in 2015 researchers from Cardiff University’s journalism school found that British press coverage was strikingly more polarised and aggressive than in newspapers across the rest of Europe.

In 2016, a disturbing analysis revealed that the Daily Express had carried 179 front pages in five years devoted to anti-migrant stories, while the Daily Mail had published 122. Through repetition, disinformation, misinformation – warnings of “hordes” to come from various war-torn or impoverished countries – and the omission of any positive material, papers incited fears of immigrants. Migrants, readers were told, were being treated to more homes, more jobs and more generous benefits than the indigenous population.

It is painful, but necessary, to remind ourselves of just some of the 301 Express-Mail propaganda pages: “Illegal migrants flood in”, “Migrant chaos all summer”, “Asylum seekers ferried around in stretch limo”, “Migrants rob young Britons of jobs”, “500,000 migrants get social housing”, “Britain’s 40% surge in ethnic numbers”.

A Daily Mail front page on migration. Photograph: Daily Mail

A Daily Mail headline from October 2014, “You can’t ignore migration now”, which was based on a single Ukip election victory.

Yet, in 2020, newspapers are, indeed, ignoring migration. Admittedly, the Daily Express is under more responsible ownership (the Daily Mirror’s publisher, Reach) while the Daily Mail is edited by a man (Geordie Greig) who no longer feels it appropriate to provoke the bigotry of a chauvinist readership.

But those factors alone, while they should be applauded, do not account for the muted coverage of immigration over the past year or so. Nor am I naive enough to think it couldn’t kick off all over again, because it’s there in the background.

Yet the undeniable truth, the sad, sick, unvarnished truth, is that migration is off the media’s central agenda for two reasons. Firstly, it is no longer a political issue. With the pro-Brexit vote having been achieved, there is no need to keep on injecting the same poison into public debate. Job done.

Secondly, seen from the newspaper editors’ perspective, it is not a sales-winning topic at present. No need to play to the gallery. There is no “value” in running anti-immigrant stories.

Given that news is what editors say it is at any given moment, then they believe it amounts to yesterday’s news.

In fact, it never was news. It was a wholly media-manufactured “crisis”. Facts, such as those detailed in a BBC briefing about immigration last week, were ignored in favour of appealing to public prejudice.

I am not doubting this prejudice exists, but it is the result of a failure by postwar governments, along with a reactionary press, to explain why Britain needed immigration and why a multicultural society should be embraced.

Instead, editors preferred to accentuate the negative. They readily published anecdotal evidence of individual misbehaviour as if it was a universal problem created by immigration. Then there were the dodgy figures, as if plucked from mid-air, that suggested Britain was about to be overrun.

Now, to get a grip on just how influential media coverage has been, note recent fascinating findings from YouGov. In its poll weeks before the referendum, when anti-migrant press coverage was at its zenith, 56% thought “immigration and asylum” were the most important issues facing Britain. Weeks later, soon after the vote, that was down to 46%.

By the following year, with the press already beginning to tail off its migration coverage, the number had fallen to 35%. Much more telling is the most recent set of findings.

Of the 24 polls in 2019, the average number of people who believed immigration was the key issue was 23%, with the latest total standing at just 20%.

In other words, the downplaying of immigration in newspapers has been mirrored by the public’s attitude towards the subject. Lack of coverage equals lack of interest. Where is that “crisis” of 2016 in 2020? It does not exist because it never did exist.

It may be, given their terminal decline, that newspapers are never able to mount such a campaign again.

So what? They have already done their worst by encouraging and exploiting deep divisions in society while splitting us off from Europe. Now that really is a crisis.