The dog-whistling and normalising of racist speech must stop, now. And there's a tried and true method for achieving that. 

The only way to effectively combat graffiti is to immediately erase it. The theory, which does work (I've tested it), is that denying the graffitists the physical proof of their work is the thing most likely to dissuade them from bothering again.

The same (tested this too) applies with online trolls. A policy of never engaging, never replying, treating them with the absolutely silent disregard that they have earned, leaves them in their echo chamber, alone and irrelevant.

New Zealand Prime Minister Jacinda Ardern understands this, at a depth that our own politicians couldn't begin to comprehend. Continuing her pitch-perfect response to Christchurch's mass murder, she said of the perpetrator: "He may have sought notoriety, but we in New Zealand will give him nothing, not even his name."

Ardern's wisdom is more urgently needed here, because we produced the killer and we are mired in misdirected anger and blame-shifting. Our problem is not how we should deal with the killer; it is what we do about the re-emergent far-right racist extremism that has returned in force to our public square.

The recrudescence of Australian xenophobia is usually dated back to the "Tampa" election of 2001, or Pauline Hanson's entry into Parliament and racist attack on "Asians" in 1996; but it really started in 1988 when John Howard, then opposition leader, called for a reduction in the rate of Asian immigration and launched a divisive migration policy called "One Australia".

Howard didn't invent xenophobia; it had only a brief 20-year respite after the dismantling of the White Australia policy.

The conventions of what it is not OK to say have fallen like dominoes over the past 30 years. The Murdoch press and TV platforms, followed by the other commercial networks, have been enthusiastic participants in the normalisation of racism. Even the ABC will interview a white supremacist like Steve Bannon and then express bewilderment at the fallout.

The Coalition parties have dabbled, dog-whistled and occasionally stepped straight into race-baiting (hello, Peter Dutton). Labor has been a more tacit contributor but, as Michael Daley just reminded us, hardly blameless.

As the laying of the foundations for race-based hate has been going on, the white supremacists have been constantly emboldened. They were always there, in the darkest recesses of our society. We used to keep them in the shadows. Now they're on Sky, Sunriseand the Senate.

We now know with 100% certainty that far and away the gravest threat to our safety is right-wing extremism. The fascists in our midst are home-grown and lethal. The critical difference between fascism and any other form of violent extremism (including Islamic terrorism) is that it seeks to subvert peaceful society from within, because its foundation is a warped belief that it is a force for preservation, not destruction. ISIS attacks from without; white supremacists believe that they are fighting to save "Western culture" from external threats to an imagined status quo. It's delusional and ridiculous nonsense. But it is only at the far end of a spectrum, at the other end of which lies Howard's and Abbott's nostalgia for a white Christian Australia that never was.

Because they are in the tent, fascists are the most dangerous threat a society can possess; far greater than that presented by the other, nihilistic cults of terror. History is clear: fascism thrives on a passive response. It loves the attention and credibility which mainstream platforming provides it; it co-opts the tools of civil society, then perverts and disposes of them.

Whether it's OK to punch a Nazi is not the point. Vigilantism isn't the answer to fascism; they love that shit. We won't beat them with street marches, eggs or ironic memes. The only answer is the unique power of the state to impose order, if necessary with violence.

The graffiti response must be applied to racist hate speech and the incitement of violence. We have hate speech laws (NSW introduced the gold standard in 2018, making it a serious crime to publicly threaten or incite violence on the basis of race or religion); they need more beefing up, but they also need to be enforced.

The calls from politicians and mainstream media for more responsibility from social media giants like Facebook aren't wrong. They do need to step up and exercise their power to help shut down the awfulness. They need to feel the weight of state power as well, with laws forcing them to do the right thing. The same applies to the telcos.

The law must be wielded, to combat the white supremacist threat. All arms of government power must be engaged to keep these fringe-dwellers down where they belong, in their fetid holes, starved of oxygen, legitimacy and an audience. The response to a racist murderer must be to erase him; his manifesto; his video. Bury him in a dark prison cell. Let his face never be seen, his voice never heard. Fraser Anning must be censured and ostracised. His contributions in the public sphere needs to be erased, not enabled.

The dog-whistling and normalising of racist speech must stop, now. It is not OK, even in America, to shout "fire!" in a crowded theatre. Nor to incite or normalise what we've just seen. This isn't a game.