Maritime dominance will shape the global order as Western naval power faces Chinese challenge

For five centuries, control of the seas has been the foundation of Western power. European empires built their dominance on it. After the Second World War, the United States and its allies inherited that maritime supremacy and used it to construct the rules-based international order that has governed global commerce, security, and diplomacy ever since. But that dominance is eroding, and the consequences will reshape how the world works.

Maritime power is not simply about having the biggest navy. It encompasses three overlapping dimensions: the ability to project military force and control shipping lanes and supply chains; the capacity to influence ports, shipyards, and the financial institutions that insure maritime trade; and what might be called strategic maritime culture—the willingness of a nation to invest in ocean power and the ability to shape how the oceans are governed. Together, these elements determine who secures global flows of goods and energy, who protects critical infrastructure, who writes the rules, and ultimately, who leads.

The post-war system is now under stress from three simultaneous pressures that reinforce one another. Geopolitically, the old status quo is being challenged through the use of force in ways that violate international law. Technologically, innovation is moving faster than military doctrine can adapt, and new tools—aerial drones, maritime drones, cyberattacks—have made offensive action cheaper and easier relative to defense. Climatically, rising temperatures are altering how equipment performs, how personnel operate, and how adversaries behave. The result is a maritime domain that is less stable, more contested, and more vulnerable than at any point in the post-war era.

This instability creates space for what security analysts call grey zone activities—hostile actions that fall short of outright war. The ocean itself is ideal terrain for such operations. It is vast, opaque, and difficult to monitor. Jurisdictions overlap or are weakly enforced. Ownership and operation of ships are buried in complex international chains of registration and crewing that obscure who is actually in control. Malicious actors can conduct attacks while maintaining plausible deniability, which complicates attribution, accountability, and the ability to deter future action.

The targets are often invisible but essential. Undersea cables carry the data that powers the global internet and financial system. Pipelines and energy interconnections move oil and gas across continents. Offshore installations extract resources. Ports and landing stations connect ships to land. These systems form transnational networks on which Western security, prosperity, and digital sovereignty depend. Recent years have seen mapping of these infrastructures, interference with data flows, and confirmed or suspected attacks on cables themselves. The aim is not necessarily to destroy but to create uncertainty, to test how the West will respond, and to erode confidence in the resilience of critical systems—all without crossing the threshold into armed conflict.

China is the primary challenger to Western maritime dominance. It is developing maritime power on a global scale, directly challenging the freedom of movement that the West has taken for granted. Iran and its proxies use geography and asymmetric capabilities to threaten energy and commodity flows through strategic chokepoints like the Strait of Hormuz, with consequences that ripple through global prices and markets. Russia conducts aggressive operations in European waters, gathering intelligence, mapping underwater infrastructure, and testing Western resolve. Its so-called ghost fleet—ships registered in ways that obscure their true ownership—exploits the opacity of maritime transport to circumvent sanctions and maintain pressure without crossing into open conflict.

What is at stake is not merely military advantage but the architecture of the international order itself. Maritime dominance has allowed Western powers to shape the rules, institutions, and practices that govern how the world works. If that dominance is lost, it will not create a vacuum so much as a different order—one shaped by China's preferences and power, one influenced by revisionist states willing to use force outside the law, one where critical infrastructure falls under private control and non-state actors gain leverage. The global order, in other words, will become less liberal, less rule-bound, and less hospitable to the interests that have defined Western security and prosperity for generations.