A new era in South Korea–US relations: ‘Pragmatic diplomacy’ and strategic dependency

South Korea’s 14th President, Lee Jae Myung, presented a comprehensive vision for the future of the U.S.-South Korea alliance during his first official summit in Washington. The Korea-U.S. relationship, a cornerstone of the regional security architecture since the Cold War, is now gaining a new dimension not only in the realm of military deterrence but also in the fields of technology, economy, energy, and cultural diplomacy.

President Lee’s speech at CSIS bears the hallmarks of a multifaceted strategy shaped by an understanding of “pragmatic diplomacy.” On one hand, Lee outlined the goal of deepening security cooperation with the U.S. in the face of North Korea’s growing nuclear capabilities and China’s rising influence. On the other hand, he is positioning South Korea as a global actor in the fields of advanced technology, the defense industry, and cultural soft power.

This new approach moves the U.S.-South Korea alliance beyond the classic framework of “military dependence,” redefining it in areas such as multipolar competition in the Asia-Pacific region, North Korea’s nuclear threats, China’s economic pressures, and trilateral cooperation with Japan. President Lee’s speech signaled that Korean diplomacy in the coming period will follow a flexible strategy that is both aligned with Washington’s expectations and centered on Seoul’s national interests.

Strategic Vision: A “Golden Age” Alliance

According to Lee, this new era aims for a multi-layered strategic partnership that transcends the traditional, security-focused understanding of an alliance:

“A forward-looking, comprehensive, and strategic alliance rests firmly on three core pillars: security, economy, and advanced technology. This ironclad alliance, built on pragmatism and the national interests of our people, will shine brightly.”

Lee’s approach aims to make South Korea a premier partner for the United States in security, economy, technology, and culture. At the heart of this strategic transformation lies the concept of “pragmatic diplomacy,” which Lee frequently emphasizes. He defined this new diplomatic approach as follows:

“It is more urgent than ever to turn crises into opportunities and to lay the groundwork for new development. The best approach we need is to respond to rapidly changing global issues with strategic insight and flexible thinking; this can be called a pragmatic diplomacy focused on national interests.”

From this perspective, Lee aims to deepen relations with the U.S. not only on a security axis but also in the areas of advanced technology, energy, semiconductors, shipbuilding, and cultural soft power. While particularly underscoring U.S. defense commitments to Korea, he also signaled that South Korea would assume a more independent and leading role in security:

“The U.S. defense commitment to the Republic of Korea and our joint defense posture remain unwavering and resolute. At the same time, Korea will assume a more leading role in ensuring security on the Korean Peninsula.”

These words envision transforming the “military dependence” axis of the alliance, which has persisted since the Cold War, and elevating South Korea to the position of an equal strategic partner to the U.S. in the Asia-Pacific security architecture.

In another sense, Lee Jae Myung’s “golden age” vision also reflects the ambition to transform South Korea from being merely a U.S. defense ally into a multidimensional global actor.

The Security Alliance: Independent Deterrence and Strategic Solidarity with the U.S.

Emphasizing that his meeting with Donald Trump exceeded expectations, Lee stated that security guarantees between the two nations were reaffirmed:

“In our summit meeting with President Trump, we agreed to modernize our bilateral alliance to make it more reciprocal and forward-looking, in line with the changing security environment.”

One of the most notable topics in Lee’s remarks was South Korea’s determination to strengthen its defense capabilities. He demonstrated a concrete commitment, especially on issues such as increasing the defense budget, transitioning to a “smart army” concept, and expanding investments in the high-tech defense industry:

“First, we will increase our defense budget, which will be used to transform the Korean military into a smart army that can prevail in future wars. We will use this budget to acquire state-of-the-art technology and military equipment.”

Lee also reaffirmed the U.S. defense commitment to the Republic of Korea, drawing attention to the importance of this cooperation for the mutual security of both countries:

“The U.S. defense commitment to the Republic of Korea and our joint defense posture remain unwavering and resolute. At the same time, Korea will assume a more leading role in ensuring security on the Korean Peninsula.”

This rhetoric can be seen as a sign that South Korea continues to trust the U.S. but is also moving toward building a more independent deterrent by enhancing its own military capabilities. By emphasizing Korea’s willingness to take on increased responsibility, President Lee also sent a subtle message to Washington:

“Korea, once a beneficiary of American aid, has now become the largest greenfield investor in the U.S. We are now an ally that shares the burden, not just one that is protected.”

In short, Lee’s security strategy aims to protect shared interests, shaped by the security of the 28,500 U.S. troops and 200,000 American citizens in Korea, while simultaneously strengthening South Korea’s own deterrence capacity. This strategy clearly sends the message to Washington: “we will lighten your load.”

The Economic and Technology Alliance

President Lee Jae Myung’s framework aims to extend the alliance beyond security, deepening it along an advanced technology and economic axis. This approach aligns with recent analyses from think tanks. A Carnegie Endowment report noted that South Korea is well-suited for the role of a “critical-technology wingman” for the U.S. and stressed the need for the two countries to “deepen their policy and supply chains” together.

South Korea maintains its technological superiority by specializing in high-value vessel types such as LNG/dual-fuel ships. Industry data shows that South Korea creates significant share and value, particularly in LNG carriers; according to South Korean maritime records, the LNG segment accounts for approximately 52% of the order book’s value. Furthermore, a CSIS study documents in detail the established institutional cooperation infrastructure for naval maintenance, repair, and modernization with the U.S. (e.g., HD Hyundai’s MSRA agreement with the U.S. Navy; Hanwha Ocean’s MRO work on USNS ships).

In 2024, Korea’s total exports reached a historic peak of $683.8 billion, of which $141.9 billion came from semiconductors, increasing their share of total exports to 21%. These figures provide a strong economic foundation for deepening advanced technology ties with the U.S.

President Lee addressed this connection in his CSIS speech:

“South Korea and the U.S. will comprehensively tackle today’s challenges, where security and the economy converge, through an advanced technology alliance where different countries cooperate to achieve mutually beneficial growth.”

Reports from Brookings and CSIS indicate that the U.S. is reconfiguring its semiconductor ecosystem following the CHIPS Act and export controls. In this context, they state that the U.S.-South Korea technology alliance requires multi-layered integration centered on joint R&D, labor policies, and supply chain security. “Public investment is at unprecedented levels… flowing into manufacturing, R&D, and workforce programs.” (Brookings Institution, 2024)

Meanwhile, the “customs tariff agreement” highlighted in Lee’s speech aims to pave the way for next-generation technology chapters and applications beyond the KORUS Free Trade Agreement. According to USTR data, total U.S.-South Korea goods trade reached $197 billion in 2024. Tariff reductions and associated investment packages implemented in the summer of 2025 can be seen as a crucial policy bridge for deepening the advanced technology partnership between the two countries:

“The customs tariff agreement signed by our countries will serve as a stepping stone to strengthen advanced technology cooperation between our two nations. The K-shipbuilding industry, equipped with the world’s strongest capabilities, will bring about a renaissance in the U.S. shipbuilding industry and create a new historic milestone for mutual prosperity.”

Cultural and Identity-Based Messages

On the global stage, South Korea is pursuing a powerful strategy not only in security and economy but also along the axis of cultural diplomacy. Elements such as K-Pop, TV series, literature, and food have transformed the country’s brand perception, becoming central to its “soft power” strategy.

In a study, Tara Shafie from the University of California points out that K-Pop artists can be used as “effective tools in public diplomacy.” According to Shafie, the government is moving beyond traditional diplomatic tools by supporting these artists as “public diplomacy ambassadors.” In her report, Shafie states, “The combined economic and cultural power of the K-Pop industry makes it one of the most significant examples of soft power today,” and the data reinforces the validity of this assertion.

President Lee Jae Myung brought this topic to the forefront in his speech, asserting that South Korea has become a global soft power hub not just in security and economy, but also in culture and democracy. Lee linked the rising global influence of Korean culture to the nation’s peaceful experience with democracy, using these words:

“Korea has established itself as a cultural powerhouse, but I believe it will soon be known not only for its cultural achievements but also as an exemplary model of democracy. The strongest foundation of the South Korea-U.S. alliance is the trust and friendship shared by our peoples. Our peoples are making each other’s lives more prosperous, and this friendship is carrying our alliance toward a bright future.”

Another prominent element in Lee’s speech was his presentation of Korea’s democratic achievements as part of its cultural soft power strategy. According to Lee, Korea’s experience of overcoming crises like coups and martial law “without shedding a single drop of blood” was highlighted as one of the elements that makes Korean culture unique in the world:

“The Korean people managed to overcome the crisis without shedding a single drop of blood. Protestors fought for democracy by singing and dancing. This is the ultimate form of democracy and people power.”

Lee stated that Korean culture has become a global, not just regional, diplomatic tool and underscored its integration with American soft power instruments. Using examples like Netflix, K-Pop, and Korean cuisine, he summarized how Korea is building a “cultural bridge” that strengthens people-to-people ties:

“Young people in Korea and the U.S. now feel a strong connection listening to the music of ‘K-Pop Demon Hunters,’ broadcast worldwide on Netflix. Just as hamburgers and pizza are no longer exclusive to America, kimbap and ramyun are no longer exclusive to Korea.” This statement highlights Korea’s strategy of deepening cultural integration with the U.S. Korean dramas, popular music, and gastronomy are presented as soft power elements that strengthen relations between the peoples of the two countries.

According to official Korean government data:

• Exports of cultural content (music, TV series, games, films) reached $9.85 billion in 2024.
• The goal is to increase this figure to $36 billion by 2030.
• According to the Brand Finance Global Soft Power Index 2025, South Korea ranked 9th in culture and heritage, while rising to 7th in the entertainment and arts category.

All these statements by Lee position South Korea not just as a “technology and security actor” but also as a cultural hub. It is clear that the aim is to foster closer ties with the U.S. not only through security but also through cultural influence and a shared identity.

A Fine Balance on China, North Korea, and Japan

President Lee addressed South Korea’s foreign policy through the lens of U.S.-China competition, North Korea’s growing nuclear capabilities, and trilateral cooperation with Japan. Lee’s messages demonstrated that Seoul is pursuing a flexible yet clear strategy within the multipolar dynamics of the Asia-Pacific. He directly responded to criticisms of “economic dependence on China” and openly stated that the traditional separation of security and economy is no longer sustainable:

“The model of ‘U.S. for security, China for the economy’ is no longer sustainable. We will adapt to U.S. export controls and the restructuring of the global supply chain,” he said.

However, Lee also emphasized that Korea would not completely burn its bridges with China due to geographical necessities, continuing:

“We cannot act contrary to U.S. policy, but due to our geographical proximity, we will focus on managing our necessary ties with China.”

This approach shows that while Seoul sends a message of strategic alignment to Washington, it aims to keep communication channels with Beijing open. Thus, South Korea is pursuing a balancing act, seeking to remain within the U.S.-led security axis while avoiding economic conflict with China.

The North Korea Problem: Deterrence + Dialogue

Regarding North Korea’s rapidly growing nuclear capabilities, Lee presented striking numerical data. These statements aim to both increase the sense of urgency in Washington and demonstrate South Korea’s strategic resolve. While Lee emphasized strong deterrence, he also stated that pressure alone would not be sufficient and that channels for dialogue must remain open. While calling on Washington for a “tougher joint policy,” he adopted a stance that avoids burning bridges with Beijing and Moscow.

“North Korea has the capacity to produce 10 to 20 nuclear weapons per year. Its intercontinental ballistic missile development is in its final stages, and its nuclear capability has increased by about 2.5 times in the last four years. We must maintain a strong deterrent against North Korea, but we cannot solve the problem with pressure alone. We must also keep dialogue channels open to avoid worsening the situation.”

Trilateral Cooperation with Japan: The Indo-Pacific Strategic Alignment

Lee specifically highlighted his visit to Japan before coming to the U.S. and reiterated the importance of the trilateral alliance. He assessed the Korea-U.S.-Japan trilateral cooperation in the context of the North Korean threat, China’s growing influence, and the Indo-Pacific security strategy as follows:

“As President Trump has consistently emphasized, trilateral cooperation between Korea, the U.S., and Japan is critically important. These three countries will respond jointly to North Korea’s nuclear and missile threats and will strengthen efforts to ensure peace and prosperity in the Indo-Pacific region.”

This statement shows that the Seoul administration is strengthening a Washington-centric bloc with Japan as part of its Indo-Pacific strategic alignment. In doing so, Seoul put forward its desire to build a trilateral line of deterrence against both North Korea’s threats and China’s regional ascent.