The 21-year-old man accused of killing 22 people in a busy Texas Walmart had one word in particular on his mind when, it is believed, he drove more than nine hours with the intention to kill Hispanic people.

“Invasion.”

In the minutes before police in the United States border town of El Paso were alerted to an active shooter, a manifesto appeared online. Investigators believe it was written by the Walmart shooter. To say the document is hate-filled would be an understatement. It borrowed key phrases from Donald Trump, making particular mention of the “invasion” that the US president’s team has spruiked in more than 2000 paid Facebook ads since the start of the year.

In the aftermath of the shooting, authorities implored the media not to publish the manifesto. They did the same after an Australian-born gunman slaughtered 51 Muslims during worship at two mosques in New Zealand earlier this year. That man, also in his 20s, was inspired by another white supremacist who gunned down nine African Americans during a church service in Charleston, South Carolina, four years ago. It is believed Christchurch served as an inspiration for the shooter in El Paso.

The argument against sharing these manifestos is the threat of contagion. In these cases, though, it was already too late. Before the right-wing extremist had even written the document, its core themes and fears existed in the mainstream press, in op-ed columns and opinions breezily offered on commercial breakfast television.

The Christchurch killer’s language focused on “white genocide” and the “replacement” of whites by others. He stressed the harm done to the “traditional family unit”; claimed “assimilation” has failed and, when he was bored of the specific anti-Islam agenda, referred to the “Left’s march through the institutions”.

And while he jettisoned the “respectable racism” of some in the commentariat, those key terms were all featured in news reports, columns and editorials in the Australian press in the year before his attack. Rupert Murdoch’s News Corp titles, particularly The Australian, offered wall-to-wall coverage of themes and subjects, including the “genocide” of white South African farmers and the queer anti-bullying program Safe Schools, which would go on to spur extremist right-wing groups.

No one is arguing these media outlets directed any of these horrific attacks. But according to new research, they did incubate an environment in which hate speech could flourish. In the end, those “respectable” debates provided fuel and gave permission.

A world-first study from Victoria University has found far-right extremist groups in Australia used saturation media narratives around Safe Schools and so-called African gangs as recruitment tools.

The empirical link between these two issues, as well as constant anti-Islam and anti-immigration rhetoric, sheds new light on the way these fringe outfits engorge themselves on mainstream press and politics.

The soon-to-be-published research shows violent extremists latch on to and are “emboldened” by news coverage and columns, which they see as adding credibility to their cause.

“I think ‘embolden’ is a really great word,” says Dr Debra Smith, a senior research fellow in terrorism and political violence at Victoria University. “It gives [far-right groups] a certain sense that these ideas are legitimate. They point to issues like this in the press to show that they are not outsiders, that they are not extreme.

“What we see in our research is that the leaders look for these strategic recruitment opportunities.”

“These guys like to set themselves up as being the brave warriors at the vanguard of this movement. Then you have these other people who go out and commit these atrocious acts of violence because they are impatient and they think this will tip things over into revolution.”

When asked if a link can be drawn between coverage of certain issues and these recruitment drives, Smith is quick to answer: “We can empirically show that. In fact, this is the first empirical evidence for that.”

Smith and her colleagues Mario Peucker and Muhammad Iqbal analysed the 12 most influential Facebook groups for far-right organisations in Victoria and studied posts and themes on these pages. They tracked the groups from when their social media footprint was established until the end of December 2017.

Although the groups all started or were based in Victoria, their fans live across the country. In all, there were almost 600,000 individuals who were members of the 12 groups, which included True Blue Crew, Love Australia or Leave, and Reclaim Australia.

Almost a third of these people are considered “active users” because they engaged with the content on these groups’ sites. The researchers split these far-right entities into three basic factions – anti-Islam, cultural superiority and racial superiority – but noted that administrators and members across all key segments are consumed by similar themes.

The researchers found that, like the extremists behind the most recent mass shooting manifestos, these far-right groups are animated by a defining narrative – that white, straight men in particular are becoming a minority in their own country, are losing control of “their” women and are unable to speak out against other cultures because of “political correctness”.

The three broad subjects that consume most of their time, according to the data from the 41,831 posts made by group administrators in the study, are nationalism and patriotism; government and politics; and Muslims and Islam. When not occupied by these, the group’s leaders shifted to secondary themes, which, ranked in order, are crime and violence; gender and sexuality; Anzac and military; immigration and, finally, multiculturalism.

This is an interesting exercise, but the researchers also dived deeper and looked at the top sources of content – the external links – that are shared in these groups. It paints an alarming picture.

The Daily Mail, the largest English-language news site in the world, tops the list. It is followed by Channel Nine’s digital products, which ranked first and second in popularity among Australians during the period covered in the research. In third place, the favoured stalking ground of neo-Nazis and far-right figures: YouTube. The Australian, with an audience many orders of magnitude smaller and its content locked behind a hard paywall, is the fourth most shared content source among far-right groups in Australia.

Smith and her colleagues are at pains to point out that these far-right groups may have core “mobilising themes” – around which they hope to whip their supporters into a frenzy – but they are opportunistic when they spot emerging issues that can be used to marshal support.

Smith and her team call these “discursive opportunities”, and two in particular stand out – the 2016 press blitz on Safe Schools, which carried into the 2017 same-sex marriage postal survey, and the reheating of a campaign about crime committed by so-called African gangs in Melbourne.

As Benjamin Law found in the research for his Quarterly Essay, Moral Panic 101, The Australian published more than 90,000 words about the Safe Schools program in just a year. The broadsheet’s African gangs campaign even came with its own special artwork – “State of Fear”. It began over the traditionally quiet December period of 2017, when attention-grabbing newspaper front pages are hard to come by.

At the time, I worked as a journalist at The Australian and would go on to watch these words line the mouths of reactionaries who suddenly had another reason to predict social decay. Earlier this year, after seven years working at the paper, I resigned my position.

As these issues took flight, the frequency with which words relating to them were used in online far-right groups spiked. Between 2015 and 2017, words such as “criminals”, “robbery” and “robbed” more than doubled in use on the pages Smith and her colleagues were tracking. Racialised words such as “gang” and “thugs” rose by 61 and 126 per cent respectively. The word “machete”, which implicitly points to foreign crime, surged by more than 1108 per cent.

During the same period, the researchers found that use of the word “transgender” soared by 1635 per cent in these groups, perfectly capturing the period during which The Australian ran its anti-Safe Schools campaign.

In a new book, The Far-Right in Contemporary Australia, Smith and Peucker make this particular point about Safe Schools in a chapter entitled “Not a monolithic movement: The diverse and shifting messaging of Australia’s far-right”.

“Many of these groups seem to have seized the opportunity when a public debate unfolded, first in 2016 around the implementation of the anti-bullying program Safe Schools, which has a strong focus on gender fluidity and identity, and second in 2017 when the public debate on legalising same-sex marriage in Australia climaxed,” they write.

It’s a basic principle of physics. When friction is removed, acceleration is easier. Media outlets do the initial lifting on an idea – white genocide, gender fluidity taking over schools – and it then becomes easier for others with an even more extremist bent to take those concepts and run with them. Coverage also provides the impression of credibility for people leaning towards those same ideas who have not yet reached a tipping point.

Smith adds another tipping point.

“These guys like to set themselves up as being the brave warriors at the vanguard of this movement,” she says.

“Then you have these other people who go out and commit these atrocious acts of violence because they are impatient and they think this will tip things over into revolution.”

The dog whistle becomes a shout and eventually a battle horn.

In the days after the Christchurch terror attacks, I spoke with Lowy Institute executive director Michael Fullilove.

“Christchurch should ... remind Australians we have allowed racism to seep deeper into our public life,” he said.

“Thirty years ago, a suggestion by a leading politician that we should slow down immigration from one part of the world was regarded as disqualifying. Would that still be the case today?

“Last year, I was shocked to see senators congratulating Senator [Fraser] Anning for a speech in which he advocated the ending of Muslim immigration and called for a ‘final solution’ to the problem of immigration.”

Anning claimed to have no idea what the phrase “final solution” meant, that he was ignorant to its historical roots as Hitler’s program to exterminate Jewish people.

The far right know the hidden power of such language better than most. To them, it is a battle song, and its lyrics are handed to them by the press. A song joined, not started.

In a later chapter of The Far-Right in Contemporary Australia, University of Newcastle professor of sociology Pamela Nilan notes the particular influence that sympathetic coverage in The Australian had on the self-proclaimed “patriot” group Soldiers of Odin Australia.

“Between The Australian and far-right websites, an identity politics of white victimhood is worked into a saga of grievance against the threatening and undeserving Muslim other, even though there is little evidence linking immigration and criminality in Australian cities,” she writes.

“The link is semiotic, with one element in the narrative tied to another by inference, not evidence.

“The twinned account of a conspiracy to enforce Sharia and a Muslim crime wave that threatens society, taken together, build an ‘apocalyptic narrative’, one that supporters can collectively accredit as representing reality.”

The fear and loathing that follow the “respectable” debates in the media are a lot harder to control and far more dangerous.