Haines pursues a political experiment - that decent people can disagree. Has this attack changed that?

But the 21st-century technology has transformed the speed and intensity with which grievance can become obsession. By Tuesday, ASIO Director-General Mike Burgess had issued a warning that read less like a routine security statement than a plea for political sanity.

“While political differences, debates and peaceful protests are essential parts of a healthy democracy, ASIO has seen direct correlations between inflamed language, inflamed tensions and acts of violence,” he said.

“I have repeatedly put on the record my concern about the use of violent rhetoric in public discourse. Words matter.”

Khalil believes social media has accelerated the breakdown of community connections, replacing everyday human interactions with increasingly isolated digital lives.

The disappearance of small encounters at local shops, sporting clubs and community gatherings has weakened social cohesion and made it harder to recognise when vulnerable people are struggling with their mental health or becoming consumed by grievances.

“We’re wired for that connection,” she said, warning that the erosion of those relationships was occurring in both profound and almost imperceptible ways, leaving communities less equipped to identify distress and intervene before it escalates.

Prime Minister Anthony Albanese has acknowledged his own side’s responsibility to lower the political temperature, arguing disagreements should be fought over ideas rather than the motivations of opponents.

One Nation’s Pauline Hanson – under pressure for her cartoon series criticised for distasteful depictions of several MPs – said violence against any elected representative, “whoever they are and whatever they stand for”, was never acceptable. Liberal leader Angus Taylor pleaded for violent attacks to not be normalised.

That test appears mighty. On Wednesday, Australian Federal Police acting Deputy Commissioner Sandra Booth delivered a confronting account of online radicalisation to a parliamentary intelligence committee.

She described a 13-year-old boy allegedly found with plans for a school shooting and vulnerable teenagers manipulated into acts of violence and exploitation through online networks.

Radicalisation and manipulation, once processes taking months or years, could now occur within days.

“Manipulation and the grievances criminals fuel can cause distrust in communities and fray our social fabric,” Booth warned.

Security agencies can investigate threats and prosecute offenders but they cannot manufacture public trust. And, as Khalil said, that trust is showing signs of strain.

Research produced by the McKinnon Foundation, found one in five Australians aged 18 to 24 could not be friends with someone holding different political views. About 9 per cent of Australians believed political violence was sometimes justified.

It exposed a troubling divide in a country where most Australians still favour democracy but only just over half are satisfied with how it works.

Britain has offered grim warnings. Labour MP Jo Cox was murdered in 2016 while meeting constituents. Conservative MP Sir David Amess was stabbed to death five years later, while this year retired MP Ann Widdecombe was brutally murdered in her rural home.

Kim Leadbeater, Cox’s sister and now a British MP, urged Australians to find common ground.

“This is your moment to think about what your politics looks like and how we can bring people together [and] find common ground,” she said in an interview with the ABC.

University of Canberra political historian Joshua Black said the question was whether this would become a defining moment in Australia’s democratic history.

“If it is a tipping point, there are really serious choices about what sort it will be,” he said.

Black argues Australia’s relative freedom from political violence owes much to a political culture built on “paperwork” rather than revolution, with compulsory and preferential voting helping to keep the political centre intact.

But the rise of social media and an increasingly combative public debate have eroded that advantage.

“I think looking at the global trends, especially what we have seen in the UK, there is cause for concern,” Black says. “The very uneasy political atmosphere for the 10 months since Bondi has been palpable.”

Temptation is to surround politicians with more security and retreat behind managed appearances. But Australia’s democratic strength has always been its accessibility: prime ministers at football matches, ministers in supermarkets, backbenchers at country shows.

Black warned the danger now was that protecting politicians could come at the expense of the accessibility that distinguishes Australian democracy.

Democracy Counts director Tom Mooney says Australia’s democracy only works if decent people were willing to put their hand up to serve their communities by representing them.

He said if this incident is shown to have been politically motivated, it will be an attack on democracy itself.

“We must do more to ensure parliamentarians are safe in their work, and reflect on the culture that is driving dangerously undemocratic behaviour,” he said.

Just before 5pm on Wednesday, outside Melbourne’s Alfred hospital, the enormity of the attack became painfully clear. Phil Haines stepped before the cameras to explain that doctors had been unable to save his wife’s second leg.

But there was something he wanted Australians to understand about his wife. Her heart and mind remained intact. Beside him stood Governor-General Sam Mostyn, who appealed for Australians to relearn how to exercise their “muscle of decency”.

“We don’t have to all agree, but we can wrestle the issue, not the person,” she said.

That evening, hundreds gathered in Wodonga carrying orange cockatoos fashioned from recycled campaign signs. McGowan had another message. She urged them not to retreat.

“My ask ... is that we don’t let violence win, that we ensure the legacy of this attack on Helen will be a stronger, more vibrant and effective democracy,” she said.

The question now is whether Australia responds by rediscovering the decency that made that movement possible.

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