Shipbuilding is not merely an industry. The seas still account for more than 90% of global trade, serving as lifelines for the transport of oil, gas, grain, and raw materials. Militarily, the oceans are the stage of hegemony. The capacity to build aircraft carriers, submarines, and naval support ships is directly tied to national security. Shipbuilding, therefore, goes beyond manufacturing; it can be called the 'core infrastructure of national strategy'.

Until the mid-20th century, the United States was the strongest force in global shipbuilding. During World War II, it built over 2,700 Liberty Ships in just five years, changing the course of the war. Yet, with postwar high-wage structures and the rise of Asian nations, the U.S. lost competitiveness in commercial shipbuilding, and today it maintains only a limited presence in military and specialized vessels.

By contrast, Korea has grown into the world’s second-largest shipbuilding power since designating shipbuilding as a national strategic industry in the 1970s. Mega container ships, LNG carriers, and oil tankers rolling out of the shipyards in Busan, Ulsan, and Geoje have become the global standard. As of 2024, the 'global shipbuilding order share' stands at China 50%, Korea 31%, and Japan 10%. Yet in the field of high-value LNG carriers, Korea commands more than 80% of global orders. China leads in volume, but Korea is unrivaled in quality and profitability.

Amid such imbalances, the United States finds itself compelled to strengthen cooperation with Korea in order to meet both military and commercial shipbuilding demand.

Korea’s shipbuilding power derives from technology, scale, and workforce.

First, 'green ship technology'. As the International Maritime Organization (IMO) tightens carbon reduction regulations, LNG-, ammonia-, and methanol-powered vessels have surged in demand. Korea holds overwhelming competitiveness here, with most of QatarEnergy’s 100-plus LNG carrier orders going to Korea’s “Big Three” shipbuilders.

Second, 'economies of scale'. Hyundai Heavy Industries’ Ulsan shipyard is the world’s largest, able to construct more than 40 vessels simultaneously. Samsung Heavy Industries in Geoje and Hanwha Ocean in Okpo also possess giant docks and advanced facilities, capable of ramping up to large-scale production as soon as contracts are secured.

Third, 'skilled labor and supply chain'. Shipbuilding is not simply welding; it requires integrated expertise in piping, electrical systems, design, and offshore plant engineering. Korea possesses over 50 years of accumulated know-how and a concentrated workforce of skilled tradesmen—capabilities that cannot be replicated in the short term.

The United States, by contrast, holds less than 1% market share in commercial shipbuilding. Projects such as the Virginia-class submarine and Ford-class aircraft carrier continue, but cost overruns and delivery delays are frequent. Recently, U.S. Navy transport ship acquisition plans have faltered due to labor shortages and shipyard production bottlenecks. In other words, 'demand is exploding, but supply capacity is fragile'—the current reality of U.S. shipbuilding.

The biggest institutional barrier to U.S. shipbuilding revival is the Jones Act of 1920. It mandates that all vessels operating between U.S. ports be built, owned, and operated by Americans. Labor unions and protectionist groups have defended it as untouchable.

President Trump, however, approaches this with his characteristic 'pragmatic protectionism.' He will not abolish the Jones Act outright, but he may consider using 'Executive Orders' to allow exceptions specifically for 'military-purpose vessels'. During his first term, Trump upheld the principle of “reviving industry on American soil,” yet also boldly bypassed regulations when necessary.

Given that current U.S. shipyards lack the production capacity to meet naval shipbuilding demand, there are forecasts that the Trump administration may turn to Korean shipyards to manufacture naval support or auxiliary vessels. This would clash with the spirit of the Jones Act, but a “temporary exception” could be set for the greater strategic goal of 'containing China and expanding naval power'.

In Trump’s trademark style, such a decision would likely be presented as a 'deal for U.S. security.' In other words, the Jones Act would remain untouched, but a loophole would be opened through Korea.

If U.S.–Korea shipbuilding cooperation takes shape, the most sensitive reaction will come from China. China already accounts for 'half of global shipbuilding orders', ranking first in volume. Shanghai and Dalian shipyards are capable of constructing both mega container ships and warships. Over the past decade, China has launched three aircraft carriers and dozens of destroyers, rapidly expanding its naval power.

Thus, if the U.S. were to build warships in Korean shipyards, China would view this not as an industrial matter but as a military provocation. Diplomatic pressure and economic retaliation against Korea could follow. These are diplomatic risks Korea must bear.

Japan, by contrast, represents an opportunity. Once the world’s number-one shipbuilder in the 1980s, Japan’s market share has now fallen below 10%, focusing on high-value specialty vessels and parts/materials. Considering the U.S.–Japan security alliance, Japan is likely to participate to some degree in a U.S.–Korea cooperation framework. A realistic model could be 'Korea’s large-vessel technology + Japan’s precision materials/parts + U.S. strategic demand.'

If such a structure takes hold, the U.S., Korea, and Japan would effectively form an alliance in maritime shipbuilding as well. This would enhance the security effect of containing China while also reshaping Northeast Asia’s maritime economic order. However, for Korea, cooperation with Japan would require overcoming domestic public opinion and historical disputes.

Four major cooperation models appear realistic:

1. 'Joint production of warships and support vessels': hulls built in Korean shipyards, final arming/assembly in the U.S.

2. 'Joint ventures and technology transfer': Korean firms investing in U.S. shipyards to boost capacity, with partial technology transfer.

3. 'Co-development of green and smart ships': collaboration on hydrogen/ammonia-powered vessels and digital twin-based ship management systems.

4. 'Joint workforce development': leveraging Korea’s skilled labor to retrain U.S. shipbuilding workers or establishing joint academies.

Yet the challenges are formidable. Protectionist sentiment and union resistance in the U.S. are strong. For Korea, risks include technology leakage and weakened industrial competitiveness. Adding to this are China’s resistance and political frictions in Korea–Japan cooperation. Shipbuilding cooperation, therefore, is not merely an economic partnership but a complex issue intertwined with 'diplomatic, security, and political risks.'

Korea is the world’s second-largest shipbuilding power, virtually monopolizing the high-value vessel sector. But full-scale cooperation with the U.S. could jeopardize this position. Hence, Korea must approach cooperation not just as order expansion but as a strategy balancing 'industrial competitiveness, technology protection, and diplomatic equilibrium.'

First, 'technology safeguards' are essential. Joint construction of military vessels could expose core designs and engineering data. Korea leads not only in naval technology but also in eco-friendly LNG and ammonia propulsion, technologies that will determine shipbuilding hegemony over the next 30 years. Even in joint projects, strict limits must be set on technology transfer, confining it to co-R\&D models.

Second, 'diplomatic balance' must be maintained. Cooperation with the U.S. inevitably invites China’s pushback. China already controls 50% of global orders and sees Korea as its chief rival. If Korea fully engages in U.S. warship building, China could retaliate in LNG markets or steel/parts supply chains. Korea must therefore pursue multi-layered diplomacy—aligning militarily with the U.S. while keeping commercial cooperation with China in civilian shipbuilding.

Third, 'industrial ecosystem reinforcement' is vital. While Korea dominates orders, labor shortages and reliance on subcontracting reveal structural weaknesses. An aging skilled workforce and lack of younger recruits are urgent issues. To handle large-scale U.S. orders, Korea must invest in workforce training, automation, and restructuring of its supply chain ecosystem.

Fourth, 'diversified clients' are necessary. U.S. cooperation offers stable orders, but overreliance on one market is dangerous. Long-term contracts with Qatar, Saudi Arabia, Norway, and European shipowners must be maintained and expanded, ensuring resilience if U.S. politics disrupt cooperation.

Finally, shipbuilding must be repositioned as a 'domestic strategic industry' akin to semiconductors and batteries. National-level investment and regulatory innovation are needed in next-generation sectors such as carbon-neutral ships, autonomous vessels, and smart yards. U.S. cooperation can provide short-term opportunities but must ultimately serve as a springboard for upgrading Korea’s shipbuilding industry itself.

Under Trump’s '“America First”' policy, the U.S. will likely preserve the Jones Act while using Executive Orders to open pathways for Korean shipyard involvement. China will resist, Japan may join as a partial partner, and Korea must simultaneously safeguard technology, balance diplomacy, and strengthen its industrial base.

In truth, “America First” under Trump emphasizes protecting domestic industry, but it also has a pragmatic side. Shipbuilding is an industry the U.S. cannot revive alone. Cooperation with Korea is inevitable, and Trump may present it as a '“deal for American security”' to reduce political costs.

For Korea, opportunities and risks coexist. It could secure stable orders and elevate its alliance status, but it must also confront technology leakage and Chinese retaliation. Japan could serve as a supplementary yet meaningful partner within a trilateral framework.

Ultimately, shipbuilding cooperation is not just an industrial contract but a 'stage to test alliance trust.' Korea’s response will shape not only its own industry but also the global shipbuilding order and Northeast Asia’s maritime strategy over the next three decades.

The global shipbuilding landscape is more than a contest for orders; it is a 'testing ground for maritime hegemony.' The intersection of U.S. strategy, Korean technology, and Japanese components creates a sea where opportunity and tension coexist. Future shipbuilding cooperation will not merely be an industrial contract but a litmus test of alliance trust and strategic foresight.