The West must draw clear red lines for responding to grey-zone aggression by China and Russia. Both adversaries have mastered operating below the threshold of open conflict to achieve their strategic aims with little consequence from Western governments. This ambiguity has eroded Western deterrence and emboldened authoritarian states to keep testing the limits of restraint.
Western leaders must define where provocation ends and aggression begins. And they must match that clarity with credible deterrent capability. Until the West decides where its red line lies, Russia and China will continue to draw it for us, as is currently the case in Europe, the Indo-Pacific and elsewhere.
ASPI’s report Unconventional deterrence in Australian strategy shines a light on this challenge, urging Australia to adopt new tools of deterrence suited to unconventional threats. The report highlights that grey-zone tactics—low-intensity actions designed to intimidate, coerce or collect intelligence—sit deliberately below the threshold of a conventional military response.
Such tactics are firmly embedded in Chinese and Russian warfare doctrine, yet Western governments have still not defined a threshold for when a response is required to such threats. As a result, authoritarian states exploit, almost daily, the West’s instinct for restraint.
Definition of a threshold is long overdue. Armed incursions into NATO airspace, deliberate interference with undersea cables, or even state-directed attacks on Western soil, such as Russia’s 2018 Salisbury poisoning, illustrate the kind of actions that should no longer be treated as ambiguous.
Strategic ambiguity is tying the West in knots. In recent months, Russian drones have repeatedly entered NATO airspace—a totally brazen act. Poland even invoked NATO’s Article 4, which allows member states to bring an issue to the organisation’s council for discussion and potentially resulting in allied decision or action. It was just the eighth time the article had been invoked in the organisation’s history. Yet little has followed.
Since then, drones have crossed into Belgium, Germany, Denmark, Norway and Romania. The crescendo came when three Russian fighter jets entered Estonian airspace for 12 minutes, before retreating when Italian jets scrambled to intercept them. Again, what has NATO’s formal response been?
China and Russia also use other grey-zone tactics to target undersea cables, threatening vital global connectivity. Damaging or cutting a cable can disable communication lines between entire continents. An accidental cut would not only disrupt data traffic but would leave the West vulnerable during any conflict.
At present, Russian vessels are loitering near Taiwan, and Chinese vessels are in the Baltic Sea. In December 2024, a Chinese vessel severed subsea cables in the Baltic while dragging its anchor along the seabed. It is not cynical to think China and Russia are colluding. More troubling still, the British government concedes it has only ‘limited capabilities’ to monitor seabed traffic.
So again, where do Western governments stand on responding robustly to such tactics? At the very least they should be developing an urgent civilian-military plan for round-the-clock maritime surveillance of vulnerable undersea cable networks. This could include naval drones to monitor and guard the seabed, as well as pre-positioned cable-repair ships ready to restore connectivity.
ASPI’s report also highlights China’s growing use of maritime militia—fishing vessels operating under direct government control—to conduct what Beijing calls the ‘people’s war at sea’. Since taking power, Chinese President Xi Jinping has subsidised provincial and local governments to significantly increase local fleets. These vessels are deployed in the South China Sea, alongside Chinese navy and China Coast Guard vessels, to promote Chinese expansionism.
This sea power is a serious regional threat, to Australia and many East and Southeast Asian states whose maritime trading routes could be easily disrupted. Australian Director-General of National Intelligence Andrew Shearer has warned that we are already engaged in grey-zone warfare with our adversaries. The task now for Western governments is to set the rules of engagement and build a deterrence that is immediate, integrated, and unconventional.
