Let’s be real for a second.
The South China Sea is a mess. Six countries with overlapping claims, decades of people yelling at each other, and the world’s busiest shipping lanes running right through the middle.
You’ve got maps that look like a toddler went wild with a highlighter, and everyone insists their version is the right one. But here’s what keeps me up at night: what happens when the rules of the game just don’t work?
That’s the question I’ve been chewing on with the North Natuna waters, better known as ‘that patch of sea where Indonesian and Vietnamese Exclusive Economic Zone (EEZ) claims collide with China PR’s Nine-Dash Line’.
It’s like a microcosm of everything that’s broken about this whole dispute. Legal regimes that major powers can ignore when it suits them.
Regional institutions trying to find consensus while everyone pulls in different directions. Sadly, economic dependencies among the parties involved make even the most principled stands feel like a bad bet.
I have been looking at this through Stephen Krasner’s international regime theory lens, and honestly? The picture isn’t pretty.
The legal framework is there, as UNCLOS 1982 gives us the foundation.
Yet, the framework only works when everyone agrees to play by the rules. It’s another story when a major power decides the rules don’t apply to them; that’s when the whole thing starts to wobble.
The Legal Foundation That’s Not Holding
UNCLOS 1982 is supposed to be the constitution for all this.
It defines maritime boundaries, establishes exclusive economic zones, and gives us mechanisms for dispute resolution. For a region where claims overlap like a messy Venn diagram, that should be the starting point.
The Philippines thought so. In 2013, they brought a case against China before the Permanent Court of Arbitration in The Hague.
The 2016 ruling was pretty clear: China’s historic rights claim within the Nine-Dash Line had no basis in international law, and none of the features in the Spratly Islands generated an EEZ of their own. Legal victory, on paper.
China’s response? “Null and void.”
They pointed to their 2006 declaration under UNCLOS Article 298, which opted out of compulsory dispute settlement for maritime boundary issues. Basically: international law applies when we want it to, and when we don’t, it doesn't. Well, thanks but no thanks.
From a regime theory perspective, this is a big deal. When a major power tells a UNCLOS tribunal to get lost, it doesn’t just undermine that one ruling.
It shakes the whole dispute settlement system. Other states are watching. And as the North Natuna case shows, they’re forced to find other ways to protect their interests: naval patrols, diplomatic protests, whatever works. Because apparently the legal arguments aren’t cutting it.
The ASEAN Balancing Act
ASEAN knows it needs to speak with one voice on this.
The 2002 Declaration on the Conduct of Parties (DOC) was the first real try, committing everyone to peaceful dispute resolution and self-restraint. But the DOC was political, not legally binding. When China kept building artificial islands anyway, it became clear the DOC had little bite.
So now we’re pushing for a legally binding Code of Conduct (CoC).
Negotiations started in earnest in 2013.
As of 2026, we’re in the second reading phase. But here’s the thing: fundamental disagreements remain.
China wants flexibility. ASEAN wants enforceability.
With ASEAN members holding divergent positions, Cambodia and Laos tilting toward Beijing, the Philippines taking a harder line under Marcos, and Malaysia hedging, consensus has been painfully slow.
The “ASEAN Way” of consensus-based decision-making often produces the lowest common denominator.
Meanwhile, China’s economic leverage over individual member states creates dependencies that make confrontation costly.
The Philippines’ shift under Duterte, and another shift under Marcos Jr. after multiple Chinese investments, is a textbook example.
As one analysis put it, “a fragmented ASEAN would allow China to exploit divisions, weakening the region’s bargaining power.”
North Natuna: A Case Study in Regime Limits
Let’s zoom in on North Natuna.
This is where Indonesian and Vietnamese EEZ claims overlap with China’s Nine-Dash Line. It’s like a perfect little snapshot of the bigger mess.
The economic stakes are enormous.
Indonesia’s proven natural gas reserves in North Natuna total 1,045.62 billion standard cubic feet, with potential reserves reaching 1,605.24 billion.
The larger Natuna D-Alpha Block contains 222 trillion cubic feet of gas, enough to power Indonesia for 30 years.
Alongside that? The fishery tonnage itself was 767,126 tons in 2017 alone.
Indonesia and Vietnam have been at odds over this since 1963. A 2019 collision between Indonesian naval vessel KRI Tjiptadi-813 and Vietnamese government ships shows how easily disagreements escalate. Twelve rounds of negotiations since UNCLOS ratification, and still no binding agreement.
Then China entered the picture.
Between 2019 and 2022, Chinese Coast Guard vessels and fishing boats appeared increasingly often in North Natuna waters.
It escalated to the point that in October 2024, Indonesia expelled a Chinese coast guard vessel that had disrupted a state energy company’s seismic survey.
Jakarta responded with diplomatic protests, legal challenges, and beefed-up naval patrols, yet repeatedly stopped short of anything that would threaten its broader economic relationship with Beijing.
Three Takeaways
So what does this all tell us? Three things, I think.
First, legal regimes have limits to enforcement. China’s rejection of the 2016 arbitration ruling has reduced UNCLOS's effectiveness in the South China Sea. Indonesia has a strong legal case but can’t enforce UNCLOS against Chinese naval power. Classic enforcement problem.
Second, economic ties complicate compliance. China is Indonesia’s second-largest foreign investor. Confrontation has real costs. This mirrors the broader ASEAN dynamic: economic dependence undermines the pull of legal commitments.
Third, issue linkage matters. Indonesia has tried to separate sovereignty issues from economic cooperation, maintaining ties while resisting encroachment. Whether that balance holds long-term remains an open question.
Where to From Here?
The South China Sea dispute isn’t going anywhere soon. But regime theory offers a framework for understanding both the limits and the value of international institutions.
UNCLOS has given us a shared legal language and a basis for dispute settlement.
The Philippines’ arbitration victory showed what regime-based resolution can achieve. But when a major power rejects a ruling, the system takes a hit, and the precedent it sets could ripple beyond the South China Sea.
For ASEAN, the CoC remains the most promising path forward. But the negotiations must navigate the gap between ASEAN’s push for binding rules and China’s preference for flexibility. And ASEAN must stay united; a divided bloc weakens the region’s bargaining power.
For Indonesia, three priorities stand out:
· Keep leaning on UNCLOS as the primary legal framework. Despite China’s challenges, Indonesia and other claimants have a stronger legal position under the Convention in North Natuna.
· Push for ASEAN collectivism in the CoC negotiations. The rules must serve all members, not just the loudest voices from the maritime countries.
· Pursue a balancing strategy, mainly by maintaining economic ties with China while strengthening regional security cooperation through joint patrols with the Philippines and Malaysia.
The deeper question is whether international regimes can adapt to the geopolitical realities they face. The answer will shape not just the South China Sea, but the future of international order itself.
Because at the end of the day, the joke isn’t that international law is a sham. The joke is that we keep trying anyway.
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Farhan Muhammad Aditomo is a researcher and analyst specializing in Asia-Pacific security, defence policy, and Indonesian foreign affairs. He holds an M.A. in International Relations from Universitas Indonesia, where he researched ASEAN multilateral negotiations and great-power dynamics in Southeast Asia. He writes in both English and Indonesian.
(JUN/GRG/QOB)