The State Department promptly released a statement calling the action ‘provocative’. Speaking in Singapore, Secretary of State John Kerry called it an ‘aggressive’ act and last week Vice President Joe Biden labelled it ‘dangerous’. ASEAN, meanwhile, half of whose member states have maritime claims overlapping with China’s in the South China Sea, issued what some considered a timid expression of ‘serious concerns’.

This combination of stern public condemnations from the US and careful moderation from ASEAN continued the pattern of regional responses to destabilising moves by the PRC in recent years. This latest episode — one of the clearest cases of unilateral provocation by China in years — illustrates the failure of both the US and regional states to deter the PRC from engaging in potentially dangerous conduct in pursuit of its sovereign claims in maritime East Asia. It is time to consider alternative approaches.

What is needed is a regional united front. The US and its allies should coordinate their public positions on regional maritime developments with ASEAN’s, while making clear that all aspects of the ‘rebalancing’ will continue. The statement released last week by Australia’s Department of Foreign Affairs and Trade, explicitly echoing ASEAN’s ‘serious concerns’ about the recent developments, demonstrates how this can be done, but the key will be securing the participation of the US.

Such a shift could offer a twofold strategic gain for states with an interest in a more stable South China Sea. First, even minor rhetorical shifts toward a united regional position on these disputes are probably more costly from China’s perspective than robust separate American and allied condemnations, which instead reassure Beijing by highlighting differences between the US and the rest of the region. Second, it could incentivise ASEAN to adopt stronger public responses to warn China of the strategic consequences of its actions.

Beijing takes ASEAN’s system of subtle signals seriously. ASEAN’s responses to regional developments are often derided as meek and even irrelevant, but this view overlooks the non-confrontational rebukes that the group already sends Beijing. The most recent example is the statement issued by the ASEAN foreign ministers in Myanmar on 10 May in response to the Sino–Vietnamese confrontation, which expressed ‘serious concerns over the on-going developments in the South China Sea, which have increased tensions in the area’. As Carlyle Thayer has suggested, this represented a subtle criticism of China and implicit support for Vietnam. More importantly, as a statement at the ministers’ level, it left room for further strengthening of this position, thus delivering an additional warning to China.

That the events in the South China Sea were on ASEAN’s agenda at all is a defiance of Beijing’s constantly reiterated demand that the South China Sea issue not be ‘internationalised’. China’s acute sensitivity to the possibility of increased ASEAN involvement was clearly shown in a statement released the same day by its foreign ministry, reminding ASEAN that ‘the issue of the South China Sea is not one between China and ASEAN’.

This brisk and testy response illustrates the extent to which China’s strategy hinges on preventing regional unity on maritime matters. With this in mind, strong public international support for the subtle positions taken by ASEAN begins to look less like appeasement and more like a way to impose strategic costs on Beijing for conduct that threatens regional stability.

A regional united front would not require acquiescence to aggression, nor would it require the US to disown its previous statements, much less its strategic ‘rebalancing’. It would, however, mean refraining from publicly condemning assertive actions in stronger terms than ASEAN is willing to adopt.

The Chinese Communist Party’s suspicious view of US intentions leads it to expect US public statements that challenge its interests and undermine its positions. It has learned to turn this to its advantage, feeding a domestic narrative of encirclement and buttressing its claim that the US approach reflects outdated Cold War thinking that runs counter to what the region wants.

But what caught Beijing off-guard when then-secretary of state Hillary Clinton declared the United States’ national interest in the South China Sea in 2010 was not simply Clinton’s high-profile statement itself but the affinity implied by its delivery at the ASEAN Regional Forum, followed by intense discussion of the issue reportedly involving 12 participants.

In contrast, when the US or its allies’ positions clearly go beyond ASEAN’s moderate positions, the PRC is reassured that its fears of regional strategic isolation remain safely over the horizon. This encourages Beijing to believe that isolation can be avoided, even if it continues with a forceful approach to defending and advancing its claims in the disputed waters.

Embracing the ‘ASEAN way’ of cautious, consensus-based diplomacy and refraining from directly apportioning blame for regional confrontations in public statements is unlikely to be a popular idea in some US-allied capitals. But there is reason to believe that adopting such an approach could help spur ASEAN to take stronger public positions against future destabilising behaviour — at least where China is the perpetrator.

While some member states see no interest in getting involved with the South China Sea issue, the balance of consensus within the group appears to be shifting.

Indonesia and Malaysia, two influential ASEAN member states, have shown heightened concerns about China’s maritime policies over the past few months, the former through a series of official public comments, the latter through concrete defence initiatives. The discussion of the issue at this month’s ASEAN Summit hosted by Myanmar suggested that Myanmar, the once-reliable Chinese ally, is now happy to see ASEAN respond to PRC provocations. Singaporean prime minister Lee Hsien-loong has made clear his belief in ASEAN involvement, while Thailand, wracked by internal chaos, is likely to accede to the majority view.

The prospect of further subtle shifts in the group’s collective stance on the South China Sea issue may make this a particularly opportune time for the US to line up behind ASEAN’s statements, helping to amplify their significance as a regional consensus.

The contrast between the US and ASEAN positions is exactly what has allowed China to believe it can get away with unilateral provocations without suffering serious costs. Creating a regional united front may offer a way for the region as a whole to impose more-effective costs on Beijing. Moreover, if it fails, it would be easily reversible. Just as ASEAN states like Vietnam and the Philippines are free to take more or less strident positions on regional affairs, Washington and its allies could depart from the regional consensus if they deemed it necessary.

This suggestion might strike many as capitulationist at first glance, but this is misguided. A regional united-front approach would leverage the basic common interest that almost all regional states share in stability and avoid coercive measures in maritime disputes. In short, the region’s much-maligned ‘lowest common denominator’ response may offer one way to create an effective deterrent against further dangerous provocations.

Andrew Chubb is a PhD student at the University of Western Australia, researching Chinese public opinion and maritime disputes in the South China Sea and East China Sea. He blogs at South China Sea Conversations.