[Special Report on the New Administration's Foreign Policy Recommendations] Vol. 1: Changes in the International Order and US-China Strategic Competition: Foreign and Security Strategy Challenges for the New Administration

I. Changes in the International Order under the Trump Administration: A Revolutionary Change in the International Order?

1. Strategy Born of Structure: A Product of the Era, Not the Individual

In the current international order, where U.S. leadership plays a crucial role, changes in the foreign and security strategy of the Trump administration's second term have a significant impact on the international order. The question is whether the U.S. strategy will bring about a revolutionary change as President Trump suggests. It is important to understand that while U.S. foreign and security strategy is significantly shaped by President Trump's individual tendencies or policy choices, it must also be understood against the backdrop of a structural transformation in the international order that the U.S. faces. In other words, even if Trump had not returned to the presidency, or if the Biden administration had continued, the U.S. would have faced the national task of readjusting its hegemonic order. Trump's second-term strategy can be seen not as an exceptional foreign policy, but as an adjustment attempt stemming from the structural situation in which the U.S. finds itself.

2. Hegemonic Strategy Fatigue: The Cost of Hegemony

The hegemonic order that the United States has built since World War II was a unique system that provided substantial order to the anarchic international society by supplying vast international public goods. The U.S. has endured an abnormal structure of maintaining the international order with its own resources, which can be considered an exceptional form in modern international political history. This system contained tensions between maintaining hegemony and economic burden, and unilateral adjustments resulting from these tensions have repeatedly occurred. For example, the dismantling of the gold standard during the Nixon era and the Reagan administration's military buildup and strong dollar policy can all be interpreted as instances where the U.S., as the hegemonic power, sought to rebalance between internal burdens and external responsibilities.

Today, the United States is once again in the midst of such an adjustment period. However, the current adjustment differs from the past in that it is appearing in a much more profound and structural form, rather than being a mere repetition of cyclical adjustments. Specifically, today's unipolar hegemony faces three structural challenges. First is the surge in demand for international public goods. The demand for solutions to complex crises such as terrorism, pandemics, and climate change is concentrated on the hegemonic power, and it is becoming clear that merely maintaining the existing order is insufficient to respond to these complex crises. Second is the increase in international instability due to globalization. The neoliberal global economic system has exacerbated wealth inequality and social divisions, and integrated global supply chains tend to amplify geopolitical risks. This exposes the limits of stability provided by the existing U.S. hegemonic order and raises doubts about the sustainability of hegemonic leadership. Third is the rise of strategic competitors like China. China's rise goes beyond mere economic growth and constitutes a substantial challenge to U.S. hegemony across security, norms, technology, and industrial systems. This re-emerges the logic of balance of power and demonstrates that a structural challenge to the U.S.-led unipolar hegemonic structure is becoming a reality.

3. Three Conflicting Objectives

These challenges necessitate a redefinition of the strategic direction of U.S. foreign policy, rather than mere policy adjustments, and the Trump administration's foreign and security strategy emerges as one response to these issues. The Trump administration's second term seeks to simultaneously pursue the reconstruction of its hegemonic economic base and the maintenance of global leadership, while domestically reducing systemic vulnerabilities and building the political and economic foundations necessary for foreign policy. The problem is that these objectives conflict, inevitably creating tensions between them. For example, the realistic concern is that sustained economic pressure on allies could weaken the credibility and cooperative basis of U.S. security strategy. Overly pursuing global leadership could increase the U.S. economic burden, weakening public support and the domestic economic base.

Increased economic pressure could lead allies to pursue independent nuclear armament or alignment strategies with adversaries, which could result in significant losses to U.S. strategic interests.

4. A Test Bed for Hegemonic Redesign

The uniqueness of the Trump administration's second-term strategy is even more pronounced when compared to previous administrations. The Trump administration has chosen a unilateral approach that prioritizes immediate U.S. interests and the contributions of other countries, rather than focusing on the stability or institutional consistency of the international order. This strategy clearly differs from traditional U.S. foreign policy, which emphasized alliances and norms. It is important to note that this approach stems not only from Trump's personal temperament or political inclinations but, more fundamentally, reflects the accumulated fatigue of the government and the public regarding the maintenance of hegemony, stemming from the U.S.'s domestic political and economic structures. Over the past approximately 30 years of the unipolar system, the American public has developed a strong perception that they have been maintaining the world order at immense cost to their nation, leading to the rise of anti-hegemonic nationalism politically. Trump is the figure who has clearly politicized and institutionalized this trend.

Against this backdrop, the Trump administration's second-term foreign and security strategy can be understood as a form of political experiment. It is not a simple strategic adjustment but an attempt to fundamentally redesign the maintenance of U.S. hegemony itself, and in the process, it inevitably clashes with the existing coherence of foreign and security policy. Approaches such as traditional U.S. alliance strategy, multilateral leadership, and the construction of a normative order are all subject to re-examination based on the criteria of 'mutual contribution' and 'burden sharing.'

While Trump's strategy may be a choice for internal reorganization of U.S. power and resources in the short term, it could be a harbinger of structural transformation aimed at redefining the U.S.-led international order in a different way in the long term. Trump's second-term foreign and security strategy should be understood not as a revolutionary break, but as an explosive manifestation of accumulated fatigue and a painful adjustment for the evolution of hegemony. It is likely to have profound implications for the future direction of U.S. foreign policy, the nature of the international order, and the structure of alliances, with Trump's second term serving as a preview and laboratory for this transition.

5. Trump's First 100 Days Security Policy in Second Term: A Parallel Strategy of Economic Recovery through 'Reduced Intervention' and 'Maintaining Hegemony'

The security strategy of the Trump administration's second term pursues two conflicting objectives—strengthening the domestic economic base and maintaining global leadership—within a complex structure. To address these dual tasks, the U.S. is adjusting its strategy to reduce its burden by decreasing intervention in international conflicts, while simultaneously maintaining its negotiating power and military deterrence. During Trump's first term, strategic consistency was secured through official documents such as the NSS (2017) and the Indo-Pacific Strategy (2019). However, in the second term, the politicization of the cabinet with loyalists and the reduction of the strategic community have weakened the systematic nature and consistency of policy production. Despite signaling a reduction in intervention, contradictory actions continue, with selective interventions attempted in various regions such as the Middle East, Ukraine, and the Taiwan Strait. Simultaneously, the rise of the trend of neo-realist restraint is leading to a strategy that seeks military distancing and cooperation frameworks with regional great powers.

The U.S. willingness to secure strong deterrence through sustained intervention in regions like Ukraine, the Middle East, India-Pakistan, and the Korean Peninsula is weakening. Russia, China, and North Korea are exploiting this as an opportunity for expansion. They advocate for the 'restoration of multilateralism,' but many countries view this as an attempt to expand their spheres of influence, widening the gap in interpretation with the existing liberal order. Regarding security based on future advanced technologies, the Biden administration continued its decoupling policy to maintain superiority in advanced technology security. However, in Trump's second term, the strategic coherence between economy, technology, and security is lacking, and policy consistency is wavering due to a focus on short-term gains.

The Ukraine war and changes in European strategy are evident in mineral agreements linking economic security and security. However, the lack of clarity in security commitments is stimulating Europe's demand for strategic autonomy. The idea of a NATO alternative remains unlikely to be realized, and the credibility of the nuclear umbrella is also weakening. The Trump administration's critical support for Israel, the tension and strategic disagreements between Netanyahu and Trump, and the uncertain prospects for the revival of the Iran nuclear deal symbolize the weakening of U.S. mediation capabilities.

Ultimately, it is difficult to definitively label the Trump administration's foreign and security strategy as revolutionary. While the strategic objectives remain consistent, the approach and tactics are distinctive. It remains uncertain whether these changes will entail a transformation of the entire international order. In specific security strategies, a security vacuum is being created through reduced intervention to promote U.S. economic recovery, and whether the U.S. will later reverse this will depend on the changing roles of allies and the success of the U.S. economic strategy. The prospects for the U.S. economic recovery strategy, centered on tariffs, are currently very unclear and uncertain. There are limitations to achieving security objectives through economic means, and the future response of mainstream U.S. defense forces and their relationship with President Trump will also play a significant role.

II. Trump's Second Term China Security Strategy and the Realignment of the ROK-U.S. Alliance

1. Strategy of Re-prioritization

The preliminary U.S. defense strategy guidance released in the first half of 2025 shows a structural shift in the U.S. geopolitical defense line. Key elements include strengthening the defense of the Western Hemisphere, focusing on the 'near abroad' regions surrounding North America such as Mexico, Canada, Greenland, and the Panama Canal, enhancing border security, and deterring China's expansion of influence. This can be interpreted as a tendency to shift the strategic focus from traditional forward defense lines in Europe and East Asia to direct homeland defense.

Furthermore, the U.S. is pursuing strategic concentration, recognizing the reality that it cannot simultaneously engage in more than one war. To this end, instead of dispersing military power and budget, it is adjusting strategic priorities to concentrate deterrence and capabilities on key competitors like China. This structural realignment directly leads to demands for burden-sharing of defense costs and strengthening of independent defense capabilities from allies, and it becomes the background for a shift from a strategy of unilateral U.S. execution to an alliance-centric strategy.

2. Strategy of Denial Against China and Prevention of Second Island Chain Expansion

The concept of Elbridge Colby's 'Strategy of Denial' is at the core of the Trump administration's second-term defense strategy. Colby argues that preemptively blocking the regional rise of military hegemons is essential for maintaining U.S. hegemony, and that the U.S. must never allow China to establish military hegemony within the island chains, i.e., within its own region. This logic is concretized into a deterrence strategy that emphasizes the contributions of allies located within the first island chain.

However, recently, cracks have appeared in the will for independent defense within Taiwan, and fatigue and skepticism about defending Taiwan are spreading within the U.S. As a result, there are concerns that the U.S. strategic defense line may retreat from the first island chain to the second. This makes South Korea's strategic position even more important. If the island chain retreats, South Korea will inevitably bear a greater burden as a forward base for deterring China.

3. 'Transfer of Deterrence': Strategic Shift in the ROK-U.S. Alliance Structure

The U.S. perceives North Korea not as a short-term military threat, but as a long-term deterrence challenge. While the possibility of a threat to the homeland exists after the declaration of nuclear armament completion, the mainstream assessment is that its actual capabilities are still limited. In the Trump administration's second term, a strategy of gradually transferring the main axis of deterrence against North Korea to South Korea is being materialized. The U.S. proposes that South Korea possesses substantial deterrence capabilities based on its combined forces and operational control system, and that South Korea should take the lead in military deterrence against North Korea in conventional forces. Currently, the guarantee of extended nuclear deterrence against North Korea is being maintained.

Crucially, signs of a functional change in the U.S. Forces Korea (USFK) are strengthening. In the past, deterring North Korea was the primary mission, but in the future, its role as a strategic asset for deterring China is being highlighted. The concept of 'strategic flexibility' is being translated into actual policy, raising the possibility of diverting some USFK forces or equipment in case of a Taiwan contingency, as well as various logistical support. This implies that the purpose of the USFK's presence is expanding from the defense of the Korean Peninsula to the maintenance of the East Asian order.

In this process, the issue of cost-sharing is becoming important. However, from the perspective of the U.S. government, this is being approached as a purely economic matter, rather than an issue of alliance trust. The reduction or maintenance of USFK is linked to budget and cost-sharing issues rather than military judgment, and the focus of future discussions is expected to be on strengthening deterrence capabilities and readjusting role-sharing. There is a high probability that South Korea will invest more resources, while the structure of U.S. strategic dominance will be solidified.

III. Foreign and Security Policy Challenges for the Next Administration

1. Changes in the Liberal International Order and a Co-evolutionary Liberal International Order

As the liberal international order gradually weakens, various proposals are emerging to replace it. First is the possibility of restoring the liberal international order. If the Trump administration's second-term strategy fails or becomes excessively transactional, there is a valid prospect that a U.S. return to alliance-centered multilateral cooperation could be re-established through the return of the Democratic Party or the mainstream Republican Party within the U.S. This scenario could lead to the reorganization of NATO, the restoration of U.S.-led collective leadership, and the redesign of the East Asian order after the stabilization of U.S.-China relations.

Second is the attempt at 'multilateralism without the U.S.' This proposes that middle powers and developed countries pursue new multilateral cooperation based on liberal norms, even without U.S. leadership. This model, which can be seen as a security version of CPTPP, has the strength of consensus on values and vision but suffers from a lack of strategic momentum and enforcement power. China and Russia also emphasize 'multilateralism,' but their focus on non-liberal objectives leaves little room for integration at present. Furthermore, alliances of middle powers among liberal developed countries face complex constraints such as lack of capacity, internal divisions, and U.S. opposition.

Third is the creation of a great power transactional regime. This approach seeks to stabilize the international order through the division of regions and cooperation among the top military great powers, transcending historical ties or ideologies. This framework, which is structurally and philosophically disconnected from the existing liberal order, is gradually emerging as a realistic political alternative, especially when combined with the pragmatic attitude of Trump-style diplomacy. In particular, the possibility of adjusting spheres of influence with China and Russia through informal agreements and bilateral negotiations is also being raised.

The future international order will not be one in which a single country can exercise hegemonic leadership as in the past. No country, not even the U.S. if it regains hegemony, can lead the international community alone. This is because the demand for international public goods such as climate change, pandemics, digital control, artificial intelligence, and cybersecurity has increased so rapidly. These issues require global responses and cannot be handled by the resources or political will of a single nation. The inevitable outcome of the international order is the emergence of collective leadership. The era is defined not by which country leads, but by which countries, in alliance with various developed and middle powers, manage and operate the order. In this structure, the order that South Korea desires must have a meaning beyond mere participation or security guarantees.

The order that South Korea desires is not simply multilateralism, but a co-evolutionary liberal order based on liberal norms, in which South Korea can actively participate. This order does not replicate the past unilateral, Western-centric liberalism and presupposes the active contribution and voice of middle powers in the supply of international public goods and norm formation. South Korea can play an important role here because it shares core principles of freedom, democracy, and market economy, while also being in a complex geopolitical balance.

An international structure simply called multilateralism is not meaningful in itself. What matters is the norms, principles, and values upon which that multilateralism operates. The liberal rules-based order, led by the U.S., has been a favorable environment for South Korea's stability and development, and it would be advantageous for South Korea if this could be further developed. The fact that China also emphasizes multilateralism and a rules-based order is positive. However, for China-led multilateralism to become a viable alternative international order, it must advance in a direction that guarantees the freedom and sovereignty of weaker nations.

South Korea must establish itself not as a passive recipient in these discussions about order, but as a principled partner and co-designer. The South Korean government must express expectations and demands for China to develop multilateralism in this direction, and realize this through concrete international policies and diplomatic strategies to ensure that the core principles of the liberal order are not undermined.

Future diplomacy is not merely a matter of 'survival' but of 'design.' South Korea must become a simultaneous agent of order formation and crisis management, based on its diplomatic capabilities, policy coherence, and integrated domestic leadership. While pragmatic diplomacy is important, it must be supported by diplomacy that accumulates strength in the era of advanced technology, ensuring long-term diplomatic leverage, and by order diplomacy.

2. US-China Strategic Competition and South Korea's Challenges: The Misconception of a New Cold War and Confrontation Amidst Coexistence, Interdependence Amidst Confrontation

The most crucial aspects for South Korea's response are an accurate understanding of the changing international order, confirmation of the desired future vision of the international order, and the presentation of a vision and principles for diplomatic strategy accordingly. It is a common misconception to predict the future international order as a state of extreme confrontation between the U.S. and China, a new Cold War. The Cold War of the 20th century was an era of firm bloc cohesion, inter-bloc exclusivity, and ideological confrontation. However, today's U.S.-China relationship is fundamentally different. Trade volume between the U.S. and China is reaching record highs, and countries belonging to each bloc are actively interacting with the other. We must also observe the overall changes that will result from the U.S.-China tariff negotiations. The Global South has emerged as a major variable in the international order, remaining unaligned with any bloc.

Neither country possesses ideological consistency internally, which makes it difficult to interpret the conflict between the U.S. and China as a simple ideological confrontation. The conflict between the U.S. and China is unfolding in a non-linear structure where competition and cooperation, and confrontation and coexistence, coexist. Defining this as a Cold War risks trapping South Korea in a dilemma of choosing one side. This is a policy error and logically weak. While the U.S. and China may engage in proxy conflicts centered on third countries, this is more of an issue at the individual policy level than a structural one.

The multipolar system, another envisioned international order, cannot be easily agreed upon or viewed optimistically. While the U.S. mentions prioritizing its interests within a multipolar system, and China, Russia, and North Korea pursue a multipolar world order, the prospects are uncertain. A system where three or more overwhelming great powers coexist is more likely to become a battleground of competition and conflict rather than cooperation. Realistically, it is very difficult to create and maintain agreed-upon international norms in a multipolar order. Consequently, a multipolar system is likely to result in 'multipolar disorder' rather than 'order,' which could lead to war and conflict. For border countries like South Korea, preventing war and realizing national interests within a multipolar order could be extremely difficult, thus we cannot be optimistic about the possibility of establishing a multipolar order.

Great powers interpret the multipolar order in their own ways to their advantage. China speaks of a stable multipolar world, while the U.S. proclaims a 'Great America' even within a multipolar world. However, the coexistence of multipolarity and stability, or multipolarity and a U.S.-centric order, can be contradictory, and a multipolar system could make middle power diplomacy even more difficult. We should not overlook the fact that the multipolar system itself is not peaceful, making it difficult to simply advocate for pragmatic diplomacy centered on national interests.

The U.S.-China strategic competition is not simply a technological gap or a tariff war. It is a long-term confrontation where the two countries gauge who can better protect and defend against each other's systemic vulnerabilities. The U.S. itself stands at a crossroads between reinforcing its hegemony and declining to a normal great power. Similarly, China faces internal structural crises such as real estate collapse and youth unemployment, amidst its image as a global factory and technological powerhouse.

China is building an image of a 'hopeful China' by leveraging leading companies like BYD and Huawei in areas of technological innovation such as AI, electric vehicles, and robotics. However, at the same time, the reality of a 'gloomy China' suffering from employment crises, consumption downturns, and debt also exists. In this reality where both aspects coexist, the U.S. needs to strategically understand a dual China, and an insight is required to gauge the sustainability of both countries' systems without bias towards optimism or pessimism.

China's technological advancement is evident, but the proportion of advanced manufacturing in its GDP is still around 6%, and its reliance on real estate remains high at over 17%. While its industrial structure is changing, its growth strategy, which neglects social security and the strengthening of its consumption base, exposes vulnerabilities in terms of durability and balance. The success or failure for both the U.S. and China will be determined by the resilience and structural complementarity of their internal systems, and this competition is putting the sustainability of the systems themselves, rather than technology, to the test.

The U.S.-China strategic competition is not merely a technological gap or a tariff war, but a long-term competition over which country can best protect its systemic vulnerabilities. The U.S. still has the potential to regain global hegemony, and China is attempting strategic rise while managing internal crises. However, the reality is that both countries stand at a crossroads between reinforcing hegemony and structural decline. Future competition will not be about which country grows faster, but about who can maintain and restore the stability of their system for a longer period.

In this situation, South Korea needs to strive to ensure that the U.S.-China strategic competition proceeds based on norms and rules, with the ROK-U.S. alliance as its foundation. Furthermore, a prudent diplomatic strategy is needed to preserve South Korea's strategic space, observe the situation with a long-term perspective, and prepare accordingly. What is important now is not short-term justification, but the accumulation of time that allows for both diplomatic flexibility and a voice in shaping the order.

South Korea is being asked to assume a position not merely as an ally, but as a strategic balancing axis. While the U.S. wants South Korea to secure autonomous deterrence capabilities, it also seeks to utilize the Korean Peninsula as a key hub in the East Asian security network based on the constant deployment of U.S. strategic assets, sustained extended deterrence, and the strategic flexibility of U.S. Forces Korea. This strategy imposes a dual burden on South Korea. Along with U.S. strategic adjustments, the responsibility for the practical management of regional security is being transferred to South Korea, and at the same time, the risk of preemptive exposure to tensions throughout East Asia is increasing. In particular, within the island chain structure, South Korea is positioned as the frontline for deterring China, along with Taiwan, the South China Sea, and Japan.

In this context, South Korea's strategic objectives include preventing wars, including localized conflicts between the U.S. and China, managing crises and resolving disputes through diplomatic means, securing military deterrence against North Korea amidst U.S.-China strategic competition, and seeking multi-layered security cooperation such as maintaining the Northeast Asian military status quo centered on the ROK-U.S. alliance and exploring small multilateral security cooperation. South Korea must contribute to maintaining the U.S.-centric security order while simultaneously securing its own defense autonomy and international credibility. It must seek strategic responses at the strategic crossroads between the U.S. and China, balancing identity and pragmatism, and alliance and survival. South Korea's strategy is no longer a matter of a single axis or choice, but has shifted to a matter of complex linkages and multi-layered responses. ■

■ Jeon Jae-sung, Director of the EAI Center for National Security Studies. Professor, Department of Political Science and International Relations, Seoul National University.

■ Managed and Edited by:Song Chae-rin, EAI Researcher

    Inquiries and Editing: 02 2277 1683 (ext. 211) | crsong@eai.or.kr