What drove Brenton Tarrant, the Christchurch gunman, to commit his heinous acts? It’s a question that has, understandably, occupied much media space . A key debate has been over the role of anti-Muslim hatred and its entrenchment in mainstream society.

In an open letter, Britain’s counter-terror chief, Neil Basu, called out the mainstream media for the “messaging” that fuels far-right terrorists. It’s a theme echoed by many on the left.

Rightwing commentators such as Melanie Phillips have dismissed such criticism as itself “peddling hatred, lies and incitement”. Spectator columnist Douglas Murray insisted that the only person responsible for the massacre was “the gunman himself”. But, he protested, “that hasn’t stopped all manner of people on social media… seeking to apportion blame” on people such as himself.

This was the same Douglas Murray who, two years ago, after jihadist attacks in Britain, claimed that Jeremy Corbyn was “guilty of facilitating the extremists” and that while there was only a small number of terrorists there was a “far larger number of people who provide the mood music for these people”. Presumably, “mood music” matters and the apportioning of blame is legitimate only when it comes to Islamist terrorists.

Hypocrisy is not confined to the right. Many on the left saw the Christchurch attacks as evidence that free speech had gone too far. Few, though, would have seen the Manchester Arena bombing in May 2017 or the Paris massacres of November 2015 as a “free speech issue”. Fewer still would support the likes of the Dutch populist politician Geert Wilders, who has demanded a ban on the Qur’an, which he damns as “hate speech” that leads jihadists to commit mass murder.

There are, of course, differences between Christchurch and the Manchester bombing or the terror in Paris, differences in context and causation. But double standards are no more acceptable on the left than they are in the writings of figures such as Murray. He is right that “mood music” matters. Creating or contributing to a culture that sees migrants, especially Muslim migrants, as “invaders”, insists that Muslims undermine “western values” and regards the promotion of “white racial self-interest” as a legitimate goal inevitably leads to Muslims being seen as a problem.

Tarrant's 'manifesto' is a grim clutter of anti-Muslim hatred, white identity politics, hostility to globalisation and defence of environmentalism

There is, though, no straight road from this to the horrors of Christchurch. I have written about the complex social and political roots of western jihadism. The same is true of white nationalist terror too. We need to understand, for instance, the ways in which social and political grievances become refracted through the politics of identity to take the form of hostility towards migrants and Muslims and how this can lead some to acts of terror. To see a direct line between Murray’s writing and the Christchurch killings is no more plausible than the claim that the Qur’an explains jihadism.

Tarrant’s “manifesto”, which he published online to justify his acts, is a grim clutter of anti-Muslim hatred, white identity politics, hostility to globalisation and a defence of environmentalism. The Christchurch attack, he writes, “was not an attack on diversity, but an attack in the name of diversity. To ensure diverse peoples remain diverse, separate, unique, undiluted and unrestrained in cultural or ethnic expression and autonomy.”

It’s a kind of rabid mishmash of left and right that is often found on the white nationalist fringe, as well as among jihadists. It reveals far-right terror to be a more complex phenomenon than many on the left want to believe. Many rightwing commentators, including Murray and Phillips, argue that they are not hostile to Muslims, simply critical of Islam. It’s an important distinction, but also one that’s gravely misused.

I have long argued that the very term Islamophobia is problematic because it conflates criticism of Islam and hatred of Muslims. As I wrote in a report by the anti-racist Runnymede Trust, this conflation enables both Muslims “to attack criticism of Islam as illegitimate because it is judged to be ‘Islamophobic’ ” and “permits those who promote hatred to dismiss condemnation of that hatred as stemming from an illegitimate desire to avoid criticism of Islam”.

We can see this in contemporary discussions in which those promoting hostility to Muslims as people are able to say: “Not me, guv. I’m just criticising Islam.” There’s a parallel here with the antisemitism/anti-Zionism debate. Antisemites often use anti-Zionism as cover for their odious views. At the same time, many exploit the fact of such antisemitism to damn all anti-Zionism as unacceptable and to try to close down debate.

The line is crossed when criticism of beliefs becomes transposed into prejudice about people

The line between legitimate criticism and illegitimate bigotry is crossed when criticism of ideas or beliefs becomes transposed into prejudice about people. There is, though, also a large grey area on the borderlands of bigotry in which commentators are not overtly anti-Muslim but play on themes and tropes of bigotry, such as the “colonisation” of Europe by Muslims or “the Great Replacement”, the conspiracy theory about white Europeans being replaced by non-Europeans that provided the title for Tarrant’s manifesto. “Europe will not be Europe and the peoples of Europe will have lost the only place in the world we had to call home.” No, not Tarrant in his manifesto but Douglas Murray in his bestselling 2017 book The Strange Death of Europe.

It’s not just figures on the right who inhabit this grey area. Liberals demand restrictions on Muslim immigration as a necessity to defend secular society. Social democratic parties across Europe have ramped up rhetoric against Muslims and migrants, citing a need to stem the rise of the far right. The creation of Fortress Europe, and of Fortress Australia, and their immoral immigration policies, have helped legitimise the idea of continents under siege from invading migrants.

All this is why the calls for stricter censorship to curtail anti-Muslim bigotry miss the point. The dehumanisation of Muslims and of migrants is a process that happens in many ways and through many agencies. Banning rightwing thinkers hostile to Muslims will no more stop terrorism acts than banning the Qur’an will stop jihadist fighters. Anti-Muslim bigotry was just one strand of Tarrant’s warped worldview. Should we censor, too, the identity politics and anti-globalisation sentiments that also provided the frame for his intent?

Condensing complex issues into easy solutions, imposing meaningless forms of censorship and finger-pointing at the most visible targets have been the stock responses to jihadist terror. We should not replicate that when it comes to far-right terror.

Kenan Malik is a columnist for the Observer