The Cost of Going Alone
Japan and South Korea are converging because the world is becoming too expensive to navigate alone
For decades, analysts explained Japan–South Korea relations through history: colonial memory, wartime grievances, and the diplomatic tensions that followed. These factors remain politically significant and continue to shape domestic politics in both countries. Yet history is becoming a less useful predictor of future behaviour.
The world that enabled Japan and South Korea to prosper is becoming more costly to navigate. Artificial intelligence demands vast computing infrastructure. Semiconductor leadership requires continuous capital investment. Energy security increasingly depends on access, stockpiles, and resilient supply chains. Data sovereignty requires domestic infrastructure. Technological competitiveness requires talent. Strategic autonomy requires all of the above.
For much of the post-Cold War period, advanced economies operated within a remarkably forgiving international environment. Energy could be sourced through global markets. Manufacturing could be distributed across continents. Supply chains were optimized for efficiency rather than resilience. Security guarantees reduced the need for duplication, while international institutions lowered the costs of economic participation and dispute resolution.
The system rewarded specialization. Countries did not need to build everything themselves. They only needed to excel in a handful of sectors while relying on the broader system for the rest. Japan became a leader in advanced materials, industrial machinery, and precision manufacturing. South Korea developed world-class capabilities in semiconductors, batteries, shipbuilding, and consumer electronics. Both prospered in an era where interdependence was viewed as an asset rather than a vulnerability.
That era is changing.
Supply chains are being redesigned around resilience rather than efficiency. Technologies once treated primarily as commercial goods are increasingly viewed as strategic assets. Access to semiconductors, advanced computing, energy, and critical minerals now sits at the intersection of economics and national security. Meanwhile, some of the institutions that previously reduced friction within the global economy have become less effective. The WTO Appellate Body, once central to the global trade dispute system, has been unable to hear appeals since 2019.
The result is not the end of globalization. It is the return of costs that globalization once helped conceal. As governments place greater emphasis on resilience, redundancy, and strategic capacity, the burden of maintaining technological and economic competitiveness has increased. This is the context in which Japan and South Korea are drawing closer.
Japan and South Korea face ageing populations, slower economic growth, and heavy dependence on imported energy. Both occupy critical positions within global technology supply chains. Both sit uncomfortably between the world’s two largest powers, benefiting from economic integration while navigating growing strategic competition. Neither possesses the scale to independently sustain every capability required in an era of technological rivalry and supply-chain fragmentation.
The challenge confronting both countries is not simply geopolitical. It is operational. The cost of maintaining competitiveness, resilience, and technological leadership has risen to a level where cooperation increasingly becomes a practical necessity rather than a diplomatic choice.
Artificial Intelligence and the Return of Infrastructure
Public debate often treats AI as a contest between models. Which country will produce the most capable systems? Which language models will dominate global markets? Which values will become embedded in future technologies? Yet, Tokyo and Seoul are returning to questions that sit much further upstream.
Who owns the data?
Where is it stored?
Who controls the infrastructure?
How much electricity will be required?
Who pays for it?
These are not secondary questions. They are foundational ones.
According to the International Energy Agency, data centres consumed approximately 415 terawatt-hours of electricity globally in 2024, representing roughly 1.5 percent of total global electricity demand. By 2030, that figure is expected to more than double as artificial intelligence becomes embedded across economies. At the same time, investment in data-centre infrastructure exceeded $400 billion in 2024 and continues to rise rapidly.
These numbers matter because they fundamentally alter the meaning of technological sovereignty.
A country may wish to develop sovereign AI capabilities. It may wish to host its own models, retain control over its data, and reduce dependence on foreign platforms. Yet before any of those ambitions can be realized, it must first secure access to semiconductors, electricity, capital, advanced computing infrastructure, and highly specialized talent. Long before sovereignty becomes a question of governance, it becomes a question of infrastructure.
Beyond Trilateralism
Historically, cooperation between Tokyo and Seoul was often mediated through a third party. The United States provided the strategic architecture within which disagreements could be managed, and the relationship frequently operated as part of a broader trilateral framework rather than as a deeply integrated bilateral partnership.
Today, the logic of cooperation is changing. The economics of technological competition are pushing bilateral coordination from desirable to increasingly necessary.
As the costs of maintaining technological competitiveness rise, the rationale for cooperation becomes less dependent on shared security concerns and more dependent on shared operational requirements. Artificial intelligence requires enormous capital investment. Semiconductor competition rewards scale. Energy security depends on purchasing power and supply-chain resilience. Data sovereignty requires domestic infrastructure. The ability to shape international standards increasingly depends on coalition-building.
Beneath these sector-specific pressures lies a broader economic reality. Japan and South Korea are confronting what might be described as a valley of low growth: an environment shaped by ageing populations, slower economic expansion, and rising strategic costs. The challenge is no longer how to maximize growth during periods of abundance, but how to maintain competitiveness, resilience, and strategic flexibility when resources become more constrained.
Periods of rapid growth are remarkably forgiving. Historical disputes can persist without imposing significant economic costs. Redundant systems can be maintained. Strategic vulnerabilities can remain unresolved. Growth provides enough surplus to absorb inefficiencies that would otherwise demand attention.
Low-growth environments are less accommodating. As growth slows and strategic costs rise, inefficiencies become more visible and more expensive to sustain. Governments face increasing pressure to prioritize capabilities that directly affect economic performance, technological leadership, and national resilience.
The future does not erase the past. But it changes the hierarchy of priorities. For Japan and South Korea, cooperation is becoming less a matter of diplomatic preference and more a response to the growing costs of navigating a more demanding strategic environment.
Sovereignty Made Physical
Energy security offers perhaps the clearest example of the broader shift underway.
Japan remains one of the world’s most import-dependent major economies, with approximately 95 percent of its crude oil imports originating from the Middle East. To reduce vulnerability, the country maintains more than 250 days of petroleum reserves across its government, private-sector, and joint reserve systems.
These stockpiles are often discussed as technical details of energy policy. In reality, they represent sovereignty made physical.
Storage facilities, procurement agreements, transportation networks, strategic reserves, and redundant capacity all require continuous investment. They exist not because they maximize efficiency, but because they reduce exposure to disruption. In exchange for higher costs, they provide governments with greater resilience and greater freedom of action during periods of uncertainty.
Semiconductor fabrication capacity, data centres, critical mineral supply chains, and cybersecurity systems are all being expanded in ways that would have appeared economically inefficient under the assumptions of an earlier era.
Governments are increasingly willing to accept higher expenses, duplicated capacity, and lower short-term returns in exchange for greater resilience. The result is a world in which redundancy is no longer viewed as waste, but as a strategic asset. That shift carries profound implications for countries attempting to remain competitive while navigating slower growth and rising geopolitical risk.
A New Geography of Power
What emerged from the discussions in Tokyo was more than a case for improved bilateral relations. It was evidence of a broader structural shift.
For decades, power was measured through territory, military capability, market size, and economic output. Those metrics remain important, but they increasingly rest upon a deeper foundation: the ability to generate electricity, process data, manufacture advanced technologies, secure critical resources, attract talent, and absorb disruption.
This helps explain why conversations about semiconductors, artificial intelligence, batteries, energy security, talent mobility, and international rule-making increasingly converge. They are not separate policy debates. They are different expressions of the same underlying challenge: maintaining sovereignty in a world where the infrastructure required to support it is becoming more complex, more expensive, and more strategically contested.
The significance of the Japan–South Korea relationship lies not simply in the fact that the two countries are cooperating more closely. It lies in what that cooperation reveals.
As the costs of resilience rise, sovereignty is becoming less about formal authority and more about the ability to build, finance, maintain, and secure critical systems at scale. Countries that can do so will enjoy greater freedom of action. Those that cannot will find their choices increasingly constrained by dependencies they cannot easily escape.
What is happening between Tokyo and Seoul may prove relevant far beyond Northeast Asia. As the costs of advanced technology, energy security, and industrial resilience continue to rise, more countries may discover that strategic autonomy increasingly requires strategic partnerships.
The twentieth century treated sovereignty as a political achievement.
The twenty-first is beginning to treat it as an engineering challenge.
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Thank you for the great article