Last weekend, China’s coastguard and maritime militia carried out dangerous and aggressive manoeuvres against a small Philippines boat, blocking and blasting it with a powerful water cannon.

The vessel was trying to resupply a remote Philippines armed forces garrison on Second Thomas Shoal, in the South China Sea’s Spratly Islands, within the Philippines’ undisputed exclusive economic zone.

This brazen escalation by China is a test for the Australian government’s readiness to speak up in defence of the international rules-based order, and to show support for a key security partner in Southeast Asia­—a region Can­berra has identified as critical to Australia’s interests.

At the AUSMIN meeting last month in Brisbane between Australian and US defence and foreign ministers, the two nations committed ^[1] to upholding a ‘global order based on international law’ and ‘fundamental principles of sovereignty and territorial integrity’.

They expressed their ‘strong opposition’ to destabilising actions in the South China Sea, including ‘the dangerous use of coast guard vessels and maritime militia’. They specifically denounced China’s excessive maritime claims as inconsistent with international law and reaffirmed their support for the landmark 2016 arbitral tribunal award in The Hague, which found in favour of the Philippines in its maritime legal dispute against China.

Washington reacted swiftly to the incident at Second Thomas Shoal, issuing a clear condemnation of China’s actions, simultaneously reassuring Manila and warning Beijing that any escalation to an armed attack on Philippines government vessels would be covered under the US–Philippines Mutual Defence Treaty. This was consistent with Defense Secretary Lloyd Austin’s June commitment to the 2016 arbitral tribunal ruling at the Shangri-La Dialogue when he stated: ‘It is ­legally binding, and it is final.’

By contrast, Canberra has so far refrained from issuing a statement from either the foreign affairs or defence portfolio. The Australian ambassador to Manila did tweet concern about ‘dangerous and destabilising’ actions but, unlike her US counterpart, did not name China.

AUSMIN communiqués are important, but they tend to be general and not widely read. The test was always going to be holding specific actions to account. The longer this official reticence about China is maintained, the more it calls into question Australia’s willingness to live up to its rhetoric on the South China Sea when the Philippines has unambiguously been on the receiving end of bullying and intimidation by Beijing.

It is to the government’s credit that bilateral relations with China have improved and tensions have reduced. But the formulation of ‘cooperating where we can and disagreeing where we must’ is not sustainable if the policy means trying to reduce tensions by ignoring differences. This doesn’t deter Beijing’s destabilising actions; it emboldens them.

If Australia doesn’t strongly call out such a provocative and destabilising breach of international law, one has to wonder what constitutes an issue on which we ‘must’ disagree with Beijing. Consistency is vital in international relations. In this case, it would both demonstrate Australia’s commitment to the rules-based order and signal to all countries, including China, what actions we consider unacceptable. The danger of choosing what ‘must’ be dealt with on an ad hoc basis, rather than by principle, is the same diplomatic error that led major European powers to think a default of silence and inconsistent engagement in the face of Russian aggression would eventually lead Russia’s Vladimir Putin back to the straight and narrow.

International rules either mean something or they don’t. In the valid attempt to reduce regional tensions, signing onto communiqués that few read while failing to speak up when it matters most risks reducing trust in both Australia and the multilateral system.

We stood up for the Philippines in 2016 when the tribunal ruled against Beijing, and we should do so now. This is a core issue for Manila. Less than a month ago, Philippines Foreign Secretary Enrique Manalo thanked the US and Australia for their support on the 2016 arbitral award. The Philippines has become one of Australia’s most important defence partners in the region. It was among the first to support AUKUS and has a bilateral visiting forces agreement enabling a high level of access, including Australian surveillance flights over the South China Sea. It is not in Canberra’s interests for Manila to doubt the strength of Australia’s commitment.

Failing to hold Beijing to account for maritime breaches would be another mistake in the mould of the misjudgement to end our World Trade Organization case against Beijing’s punitive tariffs on Australian barley. Abandoning the case spared China the indignity of another adverse international legal ruling that would have deterred Beijing and held it to account on economic coercion. It would also be a mistake to leave the condemnation to the US, as that serves Beijing’s strategic narrative that the issues at stake are only about great-power competition and US containment of China. We are all competing to shape the world in which we want to live—it is not a struggle limited to the US and China. Australia has a vital role by demonstrating that regional stability requires all nations to contribute.

Australia doesn’t have to fight every battle. But to win a competition, you have to play in it. The law-and-order principles set out in the AUSMIN communiqué go to the heart not just of our security and sovereignty, stretching from the seabed to space, but to the collective security of our region. If that isn’t worth standing up for, what is?