Sea power is cornerstone of economic security

As military tensions between the United States and Iran have intensified, global attention has once again turned to the Strait of Hormuz.

Conflict in the Middle East is nothing new. However, this latest confrontation carries particular significance for Korea because its survival is directly linked to this narrow maritime passage.

The Strait of Hormuz, connecting the Persian Gulf to the Gulf of Oman, stretches approximately 160 kilometers in length and narrows to only about 50 kilometers at its tightest point. However, nearly 20 percent of the world's seaborne crude oil passes through this strategic chokepoint. A substantial portion of Korea's imported crude oil also transits the strait. Any blockade or significant disruption to maritime traffic would immediately send shockwaves through the Korean economy.

Korea ranks among the world's top economies, yet it remains a classic maritime trading nation that depends heavily on overseas sources of energy and raw materials. More than 99 percent of the country's trade volume moves by sea. Oil, liquefied natural gas, iron ore, coal, grain and countless other resources essential to both industry and daily life all arrive through sea lines of communication. For Korea, the sea is not simply an option — it is the lifeline of national survival.

Despite this reality, South Korea has long underestimated the importance of maritime security. Discussions of national security have traditionally focused on North Korea's nuclear weapons and ballistic missiles to take a land-centric defense posture. While the North Korean threat remains real and serious, the challenges confronting South Korea in the 21st century extend far beyond the Korean Peninsula. A crisis thousands of kilometers away in the Middle East could be just as devastating to South Korea's economy and national security.

The recent U.S.-Iran confrontation clearly demonstrates that the concept of national security must expand beyond territorial defense to encompass economic security and maritime security. Today, national resilience depends less on the size of a country's armed forces than on its ability to secure the maritime routes upon which its economy depends.

The conflict also underscores the decisive role of naval power. The United States rapidly deployed a carrier strike group with Aegis-equipped destroyers and nuclear-powered submarines to the region, demonstrating overwhelming deterrence. Carrier-based aviation, long-range precision strike capabilities and stealthy nuclear submarines served not merely as offensive assets but as strategic instruments for safeguarding international shipping lanes. Conversely, Iran showed that naval mines, unmanned aerial systems, ballistic missiles and swarms of fast attack craft could threaten one of the world's most critical maritime chokepoints despite its conventional military disadvantages. The lesson is unmistakable: Modern naval warfare is no longer simply about destroying enemy fleets. It is about controlling maritime access, protecting commerce and preserving economic stability.

This is precisely why naval power deserves greater attention. A navy is not merely a wartime instrument. During peacetime, it protects vital sea lines of communication. During crises, it safeguards the nation's economic lifelines. In wartime, it denies an adversary freedom of action at sea. Nations possessing strong naval forces can shape crises and deter conflict, while those lacking credible maritime capabilities often find themselves reacting to events beyond their control.

History repeatedly demonstrates that nations commanding the seas prosper, while those that lose maritime dominance decline. Britain built a global empire upon maritime supremacy and the United States continues to shape the international order through unrivaled command of the world's oceans. This principle remains equally valid in the twenty-first century. Korea, now a major economic power, cannot sustain its prosperity without developing maritime capabilities commensurate with its global economic interests.

Korea must therefore adopt a strategic outlook befitting a true maritime nation. Rather than merely expanding the number of surface combatants, it should develop a blue-water navy capable of sustained long-range operations. This includes next-generation Aegis destroyers, the KDDX destroyer program, long-range maritime patrol aircraft, naval helicopters, unmanned surface and underwater vehicles and an integrated maritime operational architecture linking naval forces with the Air Force's airborne early warning aircraft, aerial refueling capabilities, space-based surveillance and cyber assets.

At the same time, Seoul should expand overseas deployments such as the Cheonghae Unit while strengthening combined exercises and intelligence-sharing with allies and partners throughout the Indo-Pacific. Maritime security cannot be achieved through national capabilities alone; it is strengthened through multinational cooperation and interoperability among like-minded maritime nations.

Among all naval capabilities, submarines remain the cornerstone of maritime deterrence. Invisible during peacetime and lethal in wartime, submarines provide unmatched strategic value. This explains why navies around the world continue to expand their undersea fleets. Korea should therefore move beyond the KSS-III program and pursue the acquisition of nuclear-powered submarines as a long-term national strategic objective. Such submarines would possess the endurance and operational reach necessary to conduct sustained surveillance and deterrence missions across the Strait of Hormuz, the Indian Ocean, the South China Sea and other sea lanes vital to Korea's economic security. Their acquisition should not be viewed merely as another weapons procurement program, but as an investment in the nation's long-term energy security, economic resilience, and strategic autonomy.

Sea power, however, extends far beyond military capability. It encompasses world-class shipbuilding, commercial shipping, port infrastructure, energy security, marine science and technology, satellite-based maritime surveillance and robust logistics support. Korea's emergence as a global defense exporter has been made possible by its internationally competitive shipbuilding and maritime industries. The next step is to translate these industrial strengths into comprehensive maritime strategy and naval power.

Today, the Strait of Hormuz poses a fundamental question to Korea: If our sea lanes were cut off tomorrow, how long could the nation endure?

Answering that question with confidence requires a strong and capable navy. In the twenty-first century, Korea's survival will not be secured solely along the Demilitarized Zone. It will depend equally on our ability to protect the maritime arteries that sustain our economy. The recent U.S.-Iran confrontation and the continuing vulnerability of the Strait of Hormuz serve as a powerful reminder that sea power is no longer a strategic option — it is an indispensable national necessity. Building Korea into a genuine maritime power must therefore become one of the nation's highest strategic priorities for the future.

Ret. Navy Captain Moon Keun-sik is professor of Graduate School of Public Policy at Hanyang University in Seoul.