Editor's note: We mistakenly published an earlier version of this article. This is the corrected text.

Tuesday’s ruling by the International Tribunal on the Law of the Sea has bought a little clarity to the problems in the South China Sea, but it has not made solving the underlying problems significantly simpler.

In a bad day for China, the Tribunal ruled that Beijing’s ‘nine-dash line’ (its claim to between 60% and 90% of the waters of the South China Sea) had no legal basis because China’s claims of ‘historic rights’ to the waters of the Sea had been rendered invalid when it signed the United Nations Convention on the Law of the Sea. The judgement went on to say that none of the Spratlys, a chain of reefs and rocks at the southern end of the South China Sea where China has recently built seven installations, were 'islands' and therefore did not generate any territorial or economic rights regardless of who occupied them. China also came in for further criticism over both its policy of blocking Philippine fishermen from plying their trade, and for its island building, which the Tribunal said had caused ‘severe’ environmental damage.

Philippine fishing crews prepare for an expedition to waters off the contested Spratlys, July 2016 (Photo: Getty images/Jes Aznar)

But although the ruling is a significant win for the Philippines, it is unlikely to have any immediate effect on the ground (or water). After the ruling, Beijing re-iterated its stance that the Tribunal had no jurisdiction and  therefore ‘the award is null and void and has no binding force. China neither accepts nor recognizes it.'

How China reacts in the coming days will be a test not just of the ruling, but also of Beijing’s broader willingness to subscribe to a rules-based order. Flouting the judgement would not only undermine the international legal system that has provided a framework for China’s rise, but it would also push the other claimants further into a corner. If they cannot negotiate an equitable solution and there is no longer an option of effective legal recourse, they are left with a binary choice of accepting that they are going to lose maritime territory they regard as integral to their national status (and in doing so losing legitimacy with their domestic constituency), or fighting.

But triumphalism on the behalf of the Philippines, other claimants or the US, let alone any attempt to impose the ruling by force, would be equally unhelpful. China has already lost face; amplifying the humiliation would be to invite retaliation and a new downward spiral in relations.

Tuesday’s verdict has drawn a legal line in the sands of the South China Sea, but it has also swept away the soft ambiguities that prevented diplomatic friction from turning to conflict. The ownership and fishing rights within the Philippines exclusive economic zone are no longer disputed, but that has created a potential collision course between Manila’s legal right to evict foreign settlers and arrest illegal fishermen, and reality; if it tries to enforce that right there is highly likely to be violence.

The Spratlys are all or in part claimed by Brunei, China, Malaysia, Taiwan and Vietnam. Currently Vietnam has outposts on at least 21 features, the Philippines on eight, China on seven, Malaysia on five, and Taiwan on one. Unscrambling the facts on the water, or finding an equitable way to cohabit, will take more than a court ruling.

Although yesterday’s award is unlikely to be the end of disagreement, if handled properly it could be the beginning of realistic negotiations. For all China’s refusal to recognise the award, it will carry moral weight that will go some way towards reducing the power asymmetry in talks about the future of the islands. 

But given the complexity of the overlapping claims between South East Asian littoral states, a series of bilateral negotiations between China and the other claimants is unlikely to lead to a sustainable solution. The natural counterparty to negotiations would be the Association of South East Asian Nations (ASEAN). Four of its members are claimants, and China’s nine-dash line overlaps with Indonesia’s claim of an Exclusive Economic Zone around the Natuna Islands. 

It is clear, however, that ASEAN is not yet ready to play this role. It is riven by differences (some of them encouraged by China) and currently lacks the negotiating capacity. But the infrastructure is there. With sufficient political will in South East Asia’s capitals, ASEAN could become a credible representative for the claimants.

The longer the search for a solution is delayed the harder it will be to achieve. Slowing regional economies are being mirrored by rising nationalism, and the political cost of the compromises that will be necessary for peace is rising with it. Even if Beijing wanted to compromise on its claims in the South China Sea, it will face a concerted domestic backlash from the shrill and powerful nationalist lobby that sets the pace in foreign policy debates.

The Tribunal’s decision has presented an opportunity to break the diplomatic stalemate in the South China Sea, but the hard work lies ahead. If a solution is to be found, all sides will have to demonstrate flexibility and an ability to manage their own domestic constituency.