By Vaibhav Agrawal

If someone would have stepped aboard a merchant vessel bound for Singapore in the late 1980s, the sea back then would have felt like open space where the laws of commerce and navigation seemed settled. Over the decades, we have witnessed that sense slip away evidently.

The waterways of the Indo-Pacific are no longer neutral corridors but rather contested strategic zones, commercial lifelines and legal fault-lines. Spend enough time where the sea meets law and policy, you come to recognize three stubborn and simple facts: commerce flows through water; power follows the capacity to keep that flow open or to interrupt it; and law! Whether written in black-letter treaties or delivered by gunboat, dredger or the quiet diplomacy of port leases, is the pivotal glue that tries (and often fails) to hold commerce and politics together.

The Indo-Pacific is where these dynamics collide with intensity. It is home to the busiest sea lanes on the planet, the deepest juridical disagreements over maritime entitlement, the most consequential infrastructure investments of the 21st century, and increasingly a new vocabulary of statecraft built around ports, cables and choke-points.

Operating System for Maritime Commerce

The United Nations Convention on the Law of the Sea (UNCLOS) is the operating system for maritime commerce: it defines baselines, exclusive economic zones, continental shelves and the legal contours that govern navigation, resource use and dispute settlement. Yet law alone does not determine outcomes. The 2016 arbitral award in the Philippines-China case illustrates that perfectly. The Permanent Court of Arbitration concluded that historic claims premised on the “nine-dash line” cannot displace maritime entitlements under UNCLOS, and it rejected Chinese claims to broad historic rights where those claims exceeded Convention limits. The award is legally significant; in practice, Beijing’s refusal to accept the tribunal’s jurisdiction and its continued activities demonstrate the limits of international law when powerful states choose political and coercive instruments over compliance.

That legal-political tension matters to commerce. Shipping companies, insurers and energy traders rely on predictable rights to navigate and mine resources. When legal clarity collapses into contested facts on the water, vessels shadowed by state coast guards, reclamation projects that alter low-tide elevations, or unilateral declaration of restricted zones, the cost of doing business rises through insurance premiums, rerouted voyages and the inefficiencies of layered regulatory compliance. That said, the dynamic is simple, law matters for commerce, but law without power is often merely a moral force; commerce manifests the consequence.

The CHOKE POINTS

No discussion of maritime commerce in the Indo-Pacific works without recognising chokepoints. The Strait of Malacca, the South China Sea, the Luzon Strait, the Lombok and Sunda passages, the Strait of Hormuz and Bab el-Mandeb are not abstract on-ramps for vessels but economic arteries. A large fraction of Asia’s energy supplies, container traffic, and seaborne trade squeezes through narrow channels. Shipping disruptions in these corridors would ripple through manufacturing supply chains and energy markets; insurers, commodity traders and governments all price risk accordingly. Industry and policy studies repeatedly stress that disruption at a few chokepoints could produce outsized global impact. To be honest, this is not a theoretical risk: regional tensions, asymmetric attacks on maritime traffic and even commercial accidents have produced tangible shocks to freight rates and energy availability.

Hence the strategic implications are obvious to any state that both imports raw materials and relies on export-led growth. For maritime importers like China, Japan and India, keeping these lines open is existential to growth models. For other states, controlling or influencing access to a choke point is a lever of political influence, a powerful incentive for both hard and soft power competition, from submarine patrols to port concessions and strategic logistics hubs.

State-Led Port Investment

Another point is that over the past two decades, the pattern of state-led port investment, whether marketed as commerce, development or connectivity, has reconfigured influence across the Indo-Pacific. China’s Maritime Silk Road and related Belt and Road Initiative projects have seen Chinese entities fund, build or operate ports from Djibouti to Gwadar, Hambantota to Colombo. Those investments are commercially rational for many recipient states but they also create dependencies: long-term leases, exclusive management contracts and sovereign debt obligations often translate into political leverage. Analysts and scholars have traced how such investments can create a network of logistical nodes that a state might draw upon for military or diplomatic advantage in a crisis.

And surely the pattern is not unique to one actor if we closely observe. Competing powers have responded with their own port diplomacy: infrastructure financing conditioned on governance standards, capacity-building for port security and integrated maritime development packages. The economic surface of these deals like berthing capacity, cranes, hinterland links etc. masks a geopolitical calculus: which flag will dock in a deeper bay when tensions rise and which naval support services will be readily available to a patron state?

Navies and Statecraft

Now if we speak of naval presence, private security and the blurred lines of authority, it is to be noted with utmost vigilance that where commerce flows, navies follow; where navies assert presence, commerce gains a layer of protection or becomes a lever in statecraft. For the United States and its partners, the Indo-Pacific has been the focus of strategic reaffirmation. U.S. policy documents emphasize the centrality of a free and open Indo-Pacific to global commerce and outline partnerships and investments aimed at preserving maritime order. The diplomatic architecture has responded: bilateral basing agreements, rotational deployments and multilateral security forums have proliferated.

Yet these are not purely naval exercises! Private security firms protect merchant vessels from piracy, navies coordinate with coast guards for law enforcement operations and regional navies expand their constabulary roles. The result is a pluralisation of authority over sea lines as commercial security is no longer the domain of states alone, and that complicates legal accountability. When a private armed team fires on a suspected pirate or a coastguard vessel detains a fishing trawler, commerce, sovereignty and legal remedies intersect in messy ways.

Undersea Cables

On the other hand we cannot ignore the physical cables that stitch the Indo-Pacific together carry nearly all intercontinental data and underpin modern commerce. These undersea arteries are strategic infrastructure in the same sense as oil pipelines. Damage, whether accidental or deliberate, to these cables can sever financial transactions, disable communications and disrupt markets. Recent analyses and incidents have increased concern about the vulnerability of cables and the geopolitical risks that follow when actors target or inadvertently damage them. States and coalitions are already building resiliency programmes, mapping exercises and protection protocols, but the reality is stark that the ocean floor is now contested not just for minerals and fishing grounds, but for the digital lifelines of commerce.

To the maritime lawyer this creates an interesting legal-strategic problem: cables are private property, but their protection is a public good. The appropriate mix of national responsibility, collective security and private sector obligation is unsettled and will be litigated, regulated and tested as the stakes for digital commerce rise.

Economics, supply chains and the political cost of interdiction

Maritime commerce is not only energy and raw material flows. One has to note that containerised trade and time-sensitive shipments dominate the modern economy. Firms optimize for efficiency; they do not optimize for geopolitics. When maritime insecurity forces reroutes that add days, or when port operations slow because of contested jurisdictional claims, the cost is borne by producers, logistics companies and ultimately consumers. Global trade forecasts emphasise modest growth in merchandise volumes, but also call attention to supply chain fragility when geopolitics intrudes. Policymakers now must weigh the tradeoffs between economic integration and strategic autonomy. Those tradeoffs are central to the “decoupling” debates we see in capital flows, technology transfers and industrial policy. 

In practice, this means states are investing not just in fleets and port capacity but in supply-chain resilience: alternative routing, stockpiling, near shoring and regional production networks. Commerce thus shapes geopolitics both by creating vulnerability (concentration of flows) and policy responses that seek to reduce that vulnerability (diversification and strategic alliances).

The human faces caught between states

Any account that reads maritime commerce purely as vessels and strategy misses the human dimension. Fishing communities grapple with exclusion zones, artificial island activities and contested fisheries that once supported livelihoods. Port cities absorb the boom and the bust of global flows as they gain jobs and foreign exchange yet may also face environmental degradation and social displacement. Legal disputes over maritime rights are not distant technicalities; they determine whether a fisher can reach traditional grounds or whether a coastal community will welcome a foreign operator for a development that brings short-term revenue but long-term obligations.

As an observer of arbitration hearings and of port negotiations, I have seen the same pattern: technical legal arguments in The Hague or diplomatic cables eventually translate into very local choices about nets and tugs, about where children play and where elders used to fish. Humanising maritime geopolitics matters because it influences domestic politics: frustrated coastal populations press governments to adopt tougher stances and domestic political imperatives feed back into interstate posturing.

But, the region has not stood idle. New frameworks aim to address precisely the hybrid threats that intertwine commerce and security. The Quad (Australia, India, Japan, United States) has pushed towards practical cooperation on maritime domain awareness, infrastructure resilience and humanitarian logistics; one of its initiatives explicitly focuses on improving maritime surveillance and information-sharing to protect commerce and reduce mis-perception during incidents. Such practical cooperation is as consequential as grand strategy because it produces routine mechanisms like shared data, interoperable procedures, joint exercises that reduce the chance that a single event spins into a crisis.

The flip side is that maritime commerce is increasingly targeted by non-state actors and asymmetric tactics. From piracy off East Africa to politically motivated attacks on commercial traffic, including incidents in the Red Sea and near the Gulf of Aden in recent years, asymmetric threats complicate the calculus for states that must both secure and regulate commerce. The use of sea-denial tactics, drone attacks on tankers and sponsored irregular forces introduces ambiguity about attribution and response. For insurers and shipowners this elevates premiums and complicates routing decisions; for states it raises the thorny question of how to respond proportionately without creating escalation. These are questions lawyers, insurers and naval planners now debate nightly in cables and backrooms. Recent incidents have shown that such threats can channel great-power involvement even when the original actors are small. The resulting securitisation of commerce reforms behavior across the board: ports add hardened berths, shipping corridors get naval escorts and cargo bookings shift in response to perceived risk.

What does this all mean for policy and for those who think they can isolate commerce from geopolitics?

A few practical implications emerge from the patterns above. First, maritime commerce cannot be treated as apolitical. Policy framed solely in economic or trade terms will be inadequate. Second, legal instruments (UNCLOS, arbitration) are indispensable but insufficient; they must be paired with credible deterrence and cooperative security measures to be effective. Third, infrastructure investments must be evaluated not only for immediate economic returns but for long-term strategic cost: who controls the facilities, what jurisdiction applies, and how resilient are those links to coercion or political pressure. Fourth, digital infrastructure under the sea needs immediate attention as a strategic asset of commerce; protecting it will require international cooperation, new norms and significant investment in surveillance and repair capacity. Finally, the human consequences of maritime geopolitics, of fishermen, port laborers and coastal communities etc. must be integrated into policy because domestic politics frequently sets the outer limits of foreign policy action.

As someone who witnesses and indulges in cases about rights to fisheries, negotiated port leases at midnight and watched cargo manifests disappear into the protocols of state security, I am struck by how often we in the legal and policy professions assume separability where none exists. The sea is a medium of law, but it is also a medium of power and human endeavor. Maritime commerce is the thread that ties together energy markets, food security, trade, digital connectivity and state legitimacy. In the Indo-Pacific, where the weight of those threads is enormous, geopolitics will be won or lost not only in capitals or on aircraft carriers but in the quiet calculus of port calls, cable maps and anchorages.

If policymakers and business leaders take one lesson from the contemporary pattern, let it be this: securing commerce requires an integrated approach including law backed by enforceable norms, cooperation backed by capability, and development backed by transparent governance. Ignore any one of those pillars and the seams that hold regional stability will fray. Build them together, and the Indo-Pacific can remain an engine of global prosperity rather than a theater of intermittent crisis.

Vaibhav Agrawal is a maritime and logistics legal professional specialising in high-value cross-border shipping, finance, and compliance. His practice covers sanctions compliance, multimodal transport disputes and cargo claims under arbitral frameworks.

Views expressed in this article are of the author and do not necessarily reflect the views of the publication, The Indo-Pacific Politics.