The rules-based global order is under siege at sea. For most of the past century, U.S. naval superiority has bolstered the cooperative maritime security framework needed to build a prosperous global economy.
No longer. Houthi rebels are waging a state-backed campaign to upend freedom of navigation in the Red Sea. In the South China Sea, China flouts international law, asserting new territorial claims and engaging in aggressive maneuvers. Retreating sea ice is opening the Arctic where a resurgent Russia presses its icebreaker advantage (both conventional and nuclear powered) against an anemic U.S. presence. The most basic rule of maritime law, that vessels must be flagged to states, is breaking down as pariah states seek to avoid sanctions, exacerbating existing challenges with flags of convenience.
As geopolitical instability grows at sea and below it, the seabed itself has emerged as a new frontier for global competition. A recent executive order from President Donald Trump further elevates the urgency of seabed security, partly in response to recent strategic Chinese moves into the nascent deep-sea mining industry. The United States has signaled a strategic shift: The ocean floor is no longer a passive frontier but a contested domain where resource competition, infrastructure security, and military capabilities converge.
Over the past two decades, rapid technological progress has transformed the feasibility of deep seabed operations. The commercialization of remotely operated vehicles and the rise of autonomous underwater vehicles now allows for precise, cost-effective missions at virtually any ocean depth.
Driven in part by the offshore oil industry’s demand for deep-water drilling, associated technologies like dynamic positioning systems have matured into reliable industrial tools. Meanwhile, decades of coordinated government and scientific mapping efforts have yielded unprecedented detail about seabed geography.
Beneath the waves, undersea warfare is already becoming a reality, exacerbating growing instability on the surface. Across Europe and the Pacific, Russia and China are pioneering pipeline and cable sabotage, a form of gray warfare meant to perfect tactics for future great power conflict. As retired Adm. James Stavridis has written, “while we certainly need to consider the challenges China poses on the surface of the South China Sea, we also need to look down to the murky depths of the bottom of the sea.”
Seabed critical infrastructure protection is thus an emergent NATO and U.S. priority. Among other actions, Trump’s executive order controversially revives the Deep Seabed Hard Mineral Resources Act, which originally passed in 1980 and allows unilateral U.S. mining of critical minerals on the high seas in contravention of the U.N. Convention on the Law of the Sea (UNCLOS). As the executive order notes, such materials are essential to both national defense and the energy transition.
The seabed is now an active theater of resource competition. Three major types of seafloor resources can feed a now insatiable national and global appetite for minerals. The closest resource to development are the polymetallic nodules of the Clarion-Clipperton Zone (CCZ) between Hawaii and Mexico, an area well beyond national jurisdiction. Located more than 4,000 meters below sea level, these nodules can provide nickel, cobalt, copper, and manganese—all needed for both civilian and military uses. The operational and legal precedent established by initial nodule mining will shape governance of other seafloor resources, which include critical minerals from rare earth elements to silver, gold, and platinum.
Under UNCLOS, governance of minerals in areas beyond national jurisdiction falls to the International Seabed Authority (ISA). The ISA has established a provisional regime allowing member states to sponsor commercial entities for mineral exploration, with nearly two dozen such contracts issued. China holds more ISA exploration contracts than any other country, including in the CCZ.
However, ISA is overdue in establishing an exploitation regime, preventing the commercial mining of seafloor resources.
In the absence of an ISA framework, inpatient states are now turning to mining opportunities in domestic waters, often without international guidance on environmental standards. The Cook Islands is one such state; earlier this year it reached a strategic agreement with China to jointly develop seafloor resources, ringing alarm bells in Washington.
The United States has not ratified UNCLOS, due to long-standing Senate objections to the treaty’s deep-sea mining provisions. Accordingly, the United States cannot legally secure an ISA permit, and legal uncertainty has hindered the development of a domestic industry.
The new offshore minerals executive order changes this with several actions, which are largely uncontroversial. First, it declares that the extraction of offshore minerals is important for U.S. economic and national security interests, namely for critical mineral security. Second, it accelerates offshore mineral development through faster permitting, technological innovation, and efforts to establish domestic processing and mineral stockpiling. And finally, it counters China’s dominance by expanding international partnerships and positioning U.S. leadership in global seabed mineral exploration and development.
With focused investment, the order could help make the United States an important player in the supply chains of energy and defense metals within a decade. A recent RAND report found that a deep-sea mining industry lead by the United States could produce enough nickel and cobalt to meet projected domestic demand by 2040.
However, the executive order also implicitly reasserts U.S. jurisdiction to authorize mining in international waters under domestic law. This would allow U.S. companies to controversially bypass the stalled ISA and begin nodule extraction in the CCZ within a couple years. Such a move into CCZ mining is highly controversial.
The primary legal issue is whether the ISA’s authority constitutes customary international law binding upon the U.S. absent formal ratification of UNCLOS; there are arguments both for and against such a proposition. Multiple states have already voiced objections to a unilateral approach, and they should not be quickly dismissed. Due diligence is needed to facilitate U.S. seabed mining efforts.
Ultimately, the emergent debate is a legal dispute whose implications and resolution need not threaten the law of the sea. Rather than escalating tensions, the United States should affirm its commitment to a transparent, science-based, cooperative approach that strengthens seabed norms while still asserting U.S. interests.
Careful diplomatic engagement and strategic partnerships to help other countries develop domestic offshore resources can reinforce the U.S. position on freedom of the seas. Such efforts should underscore that the true threats to the rules-based maritime order are Chinese expansionism, Russian sabotage, and the accelerating erosion of maritime norms by hostile state and non-state actors.
The seabed is the foundation of global telecommunications infrastructure and has been recognized as a growing vulnerability. More than 600 submarine telecommunications cables, many owned by U.S. tech firms, carry most of the world’s internet traffic. Just as overt warfare from the Houthi rebels (backed by Iranian weapons and Chinese intelligence) poses the most serious threat to freedom of navigation since World War II, such undersea infrastructure is also under growing threat.
State actors are probing the seabed’s legal and operational ambiguities to test response thresholds and gain asymmetric advantages. Over the last two years, Russia and China have engaged in covert operations to cut cables and sever regional ties, often using deniable measures such as dragging anchors from nominally commercial vessels. These efforts are at least in part a response to alleged Ukrainian involvement in the Nord Stream 2 pipeline explosion in 2022.
China recently publicly celebrated a specialized cable cutting device. Most likely it is intended to cut off the United States from its Pacific allies and isolate Taiwan during a Taiwan contingency. Russian vessels are equally capable of severing strategic links. Isolating the free world in the early stages of a global conflict can paralyze both populations and strategic response.
It is in this context that China’s strategic partnership with the Cook Islands, which started in 2018 and expanded to deep-sea mining in early 2025, is so worrying. The marine minerals of the Cook Islands sit directly atop telecommunications cables that connect the United States with Australia and New Zealand.
Similarly, it is only a matter of time before adversaries attempt to disrupt U.S. seabed mining efforts. The aforementioned RAND report includes a survey of government and industry experts that indicates several significant security concerns for the new industry, including the protection of vessels (U.S. flagged or otherwise) conducting legal seabed mining operations, or transporting U.S. critical minerals from such sites; enforcement of seabed mining claims and rights; use of deep-sea operations as cover to target submarines or cables and interfere with marine domain awareness; and mineral piracy in allied waters, such as is allegedly occurring in Papua New Guinea.
All of these efforts are being supercharged by technology, namely the trifecta of artificial intelligence, low-cost maritime drones, and deep-sea capabilities. The Russia-Ukraine war has clearly illustrated the dominance of modern war by drone platforms—the once mighty Russian Black Sea fleet has been hobbled by relatively cheap aerial drones and uncrewed surface vessels.
Drone warfare is now moving under the surface as states embrace autonomous underwater vehicles and subsea intelligent mines alike. Able to replicate the stealthy capabilities of crewed submarines at a fraction of a cost, continued advances in autonomy promise to upend maritime conflict. Individually, these technologies can serve mission sets from reconnaissance to kinetic attacks. When combined with persistent subsea acoustic networks, long-duration energy, and undersea communications, deep-sea drones can either threaten or reinforce allied supremacy beneath the waves.
The seabed is thus becoming an active military domain.
Just as we monitor orbit for anti-satellite weapons and the skies for surveillance balloons, we must now monitor underwater drones, deep-sea operations, and surveillance platforms. Adversary use of “gray zone” tactics deliberately blur lines between innocent and nefarious, demanding a clear doctrine of seabed domain awareness, deterrence, and defense.
Along with space, the seabed must be treated as the next strategic domain. That means building a full-spectrum seabed defense strategy that provides effective deterrence across four pillars: creating a Seabed Command or Joint Task Force, fusing NOAA science, Navy operations, and the Commerce Department’s industrial mandate into a single coordinated unit; investing in seabed domain awareness and attribution capabilities as a strategic analogue to our orbital surveillance or cyber infrastructure; protecting U.S.-licensed and allied seabed operators, submarine cables, and other critical infrastructure through legal, diplomatic, and, as needed, defensive capabilities; and engaging allies in shaping shared seabed governance mechanisms that restore order, promote science-based governance, repel gray zone interference, and facilitate joint technology innovation.
Broadly, these efforts must include efforts to develop technological advantages, particularly in harnessing advances in low-cost maritime autonomy.
The Trump administration’s broader maritime agenda is attempting to reshape how the United States approaches the sea. From ports to pipelines to polymetallic nodules, U.S. policy now recognizes the ocean as an arena of industrial and strategic importance. Just as the Marines are retooling for maritime conflict across Pacific islands, U.S. and allied subsea forces must prepare for a new type of seabed competition.
In the absence of effective global enforcement, the seabed is becoming a vacuum into which great powers are racing. By asserting a lawful, transparent, and standards-driven pathway to seabed security, incorporated into its broader maritime strategy with allies such as NATO, the United States can reinforce the rules-based order.
The post The Seabed Is Now a Battlefield appeared first on Foreign Policy.
