For a Renaissance scribe, Hugo Grotius is much in the news this year. That’s because he published Mare Liberum (Freedom of the Seas), precisely four centuries ago, helping usher in the golden age of Dutch sea power. Holland was the first modern sea power, possessing the full triad of foreign commerce, forward bases and merchant and naval fleets. Indeed, in some ways its rise to great power status presaged China’s maritime rise. Beijing has studied the Dutch case closely.
Grotius’ tract reaffirmed a longstanding pattern: Nations interpret international law to suit their own interests. Mare Liberum disputed European empires’ practice of barring foreign shipping from vast expanses. Spain claimed the Pacific, the Caribbean and the Gulf of Mexico; Portugal claimed the Indian Ocean and the south Atlantic, and England the waters east and south of the British Isles. Holland needed access to those waters to build up sea power of its own.
Having established footholds in the Indian Ocean at the close of the 16th century, Dutch traders wanted to consolidate and expand their position. Mare Liberum provided the intellectual firepower, portraying the high seas as the common property of mankind, where no nation could lawfully interfere with merchant shipping. Grotius took on the guardians of the status quo, seeking nothing less than to remake the maritime order in Holland’s favor.
This was a zero-sum contest; Dutch gain meant a rival power’s loss. Englishmen, Spaniards and Portuguese clung to their prerogatives. English scholar John Selden answered Mare Liberum with a treatise of his own, Mare Clausum (The Closed Sea). Selden’s work proclaimed that the sea was “not common to all men” but subject to national sovereignty. The English king was the rightful “lord of the sea” washing against British coasts.
Today’s debate over maritime law in Asia rhymes with that of Grotius’ day. Like 17th-century Holland, China craves its own golden age of sea power. It already enjoys abundant foreign commerce. Beijing is negotiating basing rights in the Indian Ocean region and extending the seaward reach of the People’s Liberation Army Navy (PLAN).
Like Grotius, Chinese leaders conscript international law as an ally, interpreting it selectively. They apply different rules to different seas. Selden’s closed-sea doctrine fits both with Chinese strategic traditions and with Chinese interests close to home, where Beijing’s power is at its apex. The waters landward of the first island chain form part of the historic Chinese periphery. These expanses can be enclosed and managed, protecting the heartland.
Andrew Nathan and Robert Ross call this a “Great Wall strategy,” founded on “the perception that one controls territory by surrounding it.” The PLA has deployed an array of shore-based weaponry, along with increasingly lethal ships, submarines and aircraft. It has unveiled a forward base on Hainan Island. And it covets Taiwan to anchor its Great Wall strategy off China’s East Asian coast.
In the Indian Ocean, where its navy remains weak, Beijing has struck a more conciliatory attitude, performing missions intended to uphold freedom of the seas or, in contemporary parlance, “good order at sea.” For instance, PLAN units have joined the multinational fight against piracy off Somalia. By most accounts, the PLAN units have worked well with foreign navies in the Gulf of Aden — including the US Navy, China’s main rival in East Asia.
Again, this disparity is mostly a function of naval power and geographic distance. Beijing can interpret its authority over its exclusive economic zones in East and Southeast Asia broadly, so it does. For now, free navigation is the best Chinese leaders can hope for in South Asia, so they embrace multinational cooperation. There’s nothing unusual about this. Now as in 17th-century Europe, weaker sea powers appeal to law to restrain the strong, while strong sea powers resist legal curbs on their endeavors.
Amsterdam’s appeal to principle was not entirely altruistic. Dutch merchant oligarchs saw no contradiction between their monopoly over the carrying trade in European waters and their demand for freedom of the sea farther abroad. Once entrenched in the Indian Ocean, furthermore, the Dutch East India Co guarded its monopoly as jealously as any Portuguese shipping magnate. Legal principle bent to national interests and power.
If Dutch history is any guide, China will assert itself more forcefully in the Indian Ocean as its ability to project naval power grows, letting Beijing put steel behind its regional strategy. For a glimpse of China’s future, look to the Netherlands’ maritime past.
James Holmes is an associate professor at the US Naval War College. The views voiced here are his alone.
In the US’ National Security Strategy (NSS) report released last month, US President Donald Trump offered his interpretation of the Monroe Doctrine. The “Trump Corollary,” presented on page 15, is a distinctly aggressive rebranding of the more than 200-year-old foreign policy position. Beyond reasserting the sovereignty of the western hemisphere against foreign intervention, the document centers on energy and strategic assets, and attempts to redraw the map of the geopolitical landscape more broadly. It is clear that Trump no longer sees the western hemisphere as a peaceful backyard, but rather as the frontier of a new Cold War. In particular,
When it became clear that the world was entering a new era with a radical change in the US’ global stance in US President Donald Trump’s second term, many in Taiwan were concerned about what this meant for the nation’s defense against China. Instability and disruption are dangerous. Chaos introduces unknowns. There was a sense that the Chinese Nationalist Party (KMT) might have a point with its tendency not to trust the US. The world order is certainly changing, but concerns about the implications for Taiwan of this disruption left many blind to how the same forces might also weaken
As the Chinese People’s Liberation Army (PLA) races toward its 2027 modernization goals, most analysts fixate on ship counts, missile ranges and artificial intelligence. Those metrics matter — but they obscure a deeper vulnerability. The true future of the PLA, and by extension Taiwan’s security, might hinge less on hardware than on whether the Chinese Communist Party (CCP) can preserve ideological loyalty inside its own armed forces. Iran’s 1979 revolution demonstrated how even a technologically advanced military can collapse when the social environment surrounding it shifts. That lesson has renewed relevance as fresh unrest shakes Iran today — and it should
As the new year dawns, Taiwan faces a range of external uncertainties that could impact the safety and prosperity of its people and reverberate in its politics. Here are a few key questions that could spill over into Taiwan in the year ahead. WILL THE AI BUBBLE POP? The global AI boom supported Taiwan’s significant economic expansion in 2025. Taiwan’s economy grew over 7 percent and set records for exports, imports, and trade surplus. There is a brewing debate among investors about whether the AI boom will carry forward into 2026. Skeptics warn that AI-led global equity markets are overvalued and overleveraged
RSS