The killing of conservative activist Charlie Kirk in the United States on 10 September should jolt us all, regardless of politics or geography. But a key question is what we are jolted into doing. Should it be permissive acceptance that the US, western society and democracy are all now in such a state of decline and division from which there is no return? Or should it be a renewed conviction of our responsibility to remind the public why democracy thrives on debate and the binding forces of the very freedoms that enable individuals to choose to be different and to disagree?

It should be that renewed conviction, one that prompts an energetic public information campaign aimed at promoting the notion of agreeable disagreement, of amicable diversity of view. It should also help inoculate Australians against foreign-interference intrusions that seek to exploit disagreement. It should reinforce our alarmingly weakening social resilience.

In recent years the US has endured a grim pattern of politically motivated attacks: the 2025 murder of Minnesota Democratic legislator Melissa Hartmann and her husband, the 2022 assault on Nancy Pelosi’s husband, the shooting of Republican congressman Steve Scalise in 2017, the murder of a federal judge’s family in 2020 and threats against Supreme Court justices. The ideologies behind these attacks differ, but we see the same violent contempt for democratic process and debate. Politically motivated violence (PMV) was prevalent in previous eras. Now it’s back.

And this is not a uniquely American pathology. PMV ignores party lines and flourishes when civic debate collapses into tribal grievance. The quote misattributed to Voltaire, ‘I disapprove of what you say, but I will defend to the death your right to say it’, has become ‘I disagree with what you say, so you have no right to say it.’ Guns make the US’s incidents deadlier, but the underlying drivers of PMV—hyper-polarisation, online radicalisation and the easy weaponisation of conspiracy—are not confined to the US. Australia also needs to confront these dynamics before they metastasise here.

Australia’s director-general of security, Mike Burgess, has warned that PMV now stands alongside espionage and foreign interference as a principal national-security threat. In his 2024 Annual Threat Assessment, Burgess emphasised that spirited debate and peaceful protest were hallmarks of a healthy democracy but cautioned that anti-authority beliefs were spreading, trust in institutions eroding and inflammatory behaviour becoming normalised.

Bipartisan resolve to confront PMV, regardless of ideology, is essential. And yet, despite public statements of mourning spanning the political aisle, there has so far been little fertile ground for practical cooperation in Washington. Australia should work to prevent the same happening here while simultaneously bolstering existing cooperation with the US and other partners on shared PMV experience. This initiative should focus on lessons learned. One is the importance of politicians facing up to genuine public concerns, such as those about illegal immigration, rather than either downplaying them and letting them become fuel for division or overplaying them and directly stoking division.

Confronting all democratic partners is that the threat environment is no longer neatly partisan. Extremist violence is increasing, persistent and dynamic, cutting across ideologies and defying the old left/right buckets that politicians and the media are used to. Every time a political leader points to ‘the far right’ or ‘the far left’ as the culprit, the national conversation shrinks. Simplifying complexity into tribal blame might reassure supporter bases, but it leaves the real drivers of violence unchallenged—and gives oxygen to those who thrive on grievance, division and parochialism. It sets up two adversarial camps rather than offering a path to unity on principles even if there is disagreement on individual policies.

PMV now emerges from diverse cohorts—lone wolves, conspiracy movements, single-issue ideologues, foreign-influenced agitators—that can’t be mapped to a single side of politics or ideology. Foreign states are using information operations and online manipulation to inflame social tensions and amplify differences. The ongoing conflict in the Middle East, for example, shows that old problems—sectarian tensions, ethno-nationalism, imported grievances—remain potent. It’s precisely in this environment that foreign interference and information operations find fertile ground, eroding trust in democratic institutions and debate. They replace national unity with internecine hatred.

That makes social cohesion a core national-security asset. In his final address to the nation in 2017, president Barack Obama reflected that ‘democracy does not require uniformity. Our founders argued. They quarrelled. Eventually they compromised. They expected us to do the same. But they knew that democracy does require a basic sense of solidarity—the idea that for all our outward differences, we’re all in this together.’ Such sentiment may appear quaint in 2025, yet a society able to debate, disagree and still hold together is far harder to manipulate and more resilient to crisis moments that will inevitably arise. But the public square is eroding. Too often, disagreement is now treated as extremism. The result is a chilling of debate precisely when democratic resilience depends on it.

This is where political and strategic communication is so critical to national discourse and resilience. Australia has a proud history of national campaigns that build shared identity: the ‘Life. Be in it.’ public health campaign, the centenary-of-federation ads that taught generations who our first prime minister was, and Telstra’s promotion of unity in football under the motto ‘It’s the things that set us apart that bring us together.’ These were community-building. Importantly, none forced a view on which activities had to be done—which footy team had to be followed or which former politician was best. They promoted a stronger community in which each person could still be his or herself.

Regional partners offer contemporary examples. Singapore’s SGSecure initiative combines grassroots preparedness training, community dialogues and a relentless ‘not if, but when’ message to embed counter-terrorism and social-cohesion reflexes across society. It recognises, as Australia should, that resilience is both a domestic and foreign-policy imperative: protection against violence and against the erosion of trust that is being exploited by hostile states and individuals alike.

We need the same spirit that once underpinned ‘Life. Be In It’, but this time centred on national resilience. A campaign that celebrates democratic disagreement, inoculates against foreign manipulation and reminds Australians that unity is a choice, not a given. Bipartisan commitment to confronting PMV is a start. But, without a parallel effort to support the social fabric that extremists of all types seek to tear, it won’t be enough. The fundamental truth remains; nations are stronger together than divided. It starts with relearning that it is okay to be different in pursuit of making a difference and that debate is not the end of democracy but its core strength.