Abstract of the doctoral dissertation by Nguyen Thu Phuong

VIETNAM NATIONAL UNIVERSITY OF HANOI

UNIVERSITY OF SCIENCESOCIETY AND HUMANITIES

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Nguyen Thu Phuong

 

 

POLICY TOWARDS ALLIES IN EAST ASIA DURING THE OBAMA ADMINISTRATION - THE CASE OF SOUTH KOREA

 

 

Major: International Relations

Code: 62 31 02 06

 

 

ABSTRACT OF THE DOCTORAL THESIS IN INTERNATIONAL STUDIES

 

 

Hanoi - 2020

 

 

 

The project was completed at: University of Social Sciences and Humanities, Vietnam National University, Hanoi.

 

Scientific supervisor: Prof. Dr. Tran Thi Vinh

 

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The dissertation will be defended before the National University Doctoral Dissertation Examination Board meeting at: Faculty of Social Sciences and Humanities, Vietnam National University, Hanoi.

at [time] on [date] [month] [year] 20...

 

 

The thesis can be found at:

- National Library of Vietnam

- Information and Library Center, Vietnam National University, Hanoi

 

List of the author's scientific works

related to the Thesis

1…. (2017), “Asia Pacific in the foreign policy of the Donald Trump administration”,Electronic Communist MagazineAugust 8, 2017

2…. (2019), “Identifying the US Asia-Pacific Strategy under President Barack Obama: An Approach from a Security-Military Perspective”, Proceedings of the International Scientific Conference “Prospects for the Asia-Pacific Structure to 2025 and Vietnam's Countermeasures”, State-level project code KX.01.12/16-20, Hanoi, p. 196

3…. (2019), “Looking back at the US Asia-Pacific strategy during the Obama presidency”,Today's America Magazine, number 05 (254), pp. 13-24

4…. (2019), “Alliance Policy in the US Asia-Pacific Strategy and Current Adjustments”,Communist Magazine(921), pp. 101-106

5 Assoc. Prof. Dr. Doan Minh Huan, PhD Candidate Nguyen Thu Phuong (2019), “Guiding principles and guidelines in Vietnam's relations with the United States from 2009 to the present, Vision 2030”, Proceedings of the Scientific Conference under the National Project “Vietnam's countermeasures to the US Asia-Pacific strategy: An approach based on changing circumstances”, Hanoi, pp. 12-27

6…. (2019), “The US-Korea Free Trade Agreement and some reference suggestions for Vietnam”,Communist Magazine(928), pp. 106-111

7…. (2020), “Forward Force Deployment in East Asia: A Driving Force for the US Indo-Pacific Strategy,Communist Magazine(number 941)

 

INTRODUCTION

1. Reasons for choosing the topic

The United States has the largest global alliance system in the world. Within this network of allies spanning five continents, East Asia is a crucial link. This was clearly demonstrated under President Barack Obama's administration when the US implemented its "rebalancing" policy towards the Asia-Pacific. Accordingly, during his two terms in office, the US policy towards these regions...

Among America's East Asian allies, the US-South Korea alliance is particularly significant, with its developments having a considerable impact on regional peace, security, and cooperation. In the context of East Asia's inherent instability and the serious security challenges posed by China's powerful rise and North Korea's nuclear threat, South Korea is seen as a cornerstone of the US's "re-engagement" strategy in East Asia. Furthermore, the US-South Korea alliance – one of the most robust and enduring military alliances in the region – is expanding to become a global strategic alliance. The US-South Korea alliance not only impacts the two entities involved but also the regional and global security environment. Therefore, studying US policy toward South Korea during President Barack Obama's administration is crucial.urgencyfor identifying contemporary international relations.

2. Research Objectives and Tasks

2.1 Research Objectives

The research objective of this thesis is to clarify the policies and implementation of US policy towards its allies in East Asia during the administration of President Barack Obama (2009-2016), with a focus on the alliance policy with South Korea. Through this, the thesis evaluates the results and limitations, clarifying the characteristics of US policy towards its East Asian allies during this period.

2.2 Research Objectives: (1) Clarifying the theoretical framework of allies and the US perspective on allies; the basis for forming relations and policies toward US allies in East Asia before 2008; (2) The practical implementation of policies toward East Asian allies during the two terms of President B. Obama; (3) Clarifying the content and process of implementing policies toward South Korea by the administration of President B. Obama from 2009-2016. (4) Commenting on the characteristics of US policy toward East Asian allies during the presidency of B. Obama. From there, comparing and studying the inheritances and adjustments in policies toward East Asian allies, especially South Korea, by the administration of President D. Trump.

3. Research Subjects and Scope

3.1 Research Subjects

The subject of this thesis is the US policy toward its allies in the Eastern region.

3.2 Scope of the study

- Time frame: From 2009-2016, spanning two periods: 2009-2012 and 2012-2016 (corresponding to the two terms of President B. Obama).

- Spatial limitations: The research focuses specifically on South Korea and several US allies in East Asia (including Japan, the Philippines, and Thailand).

- Content limitations: The study focuses on US policy in the areas of security, military, and politics toward South Korea in particular, and its allies in East Asia in general.

4. Research approach and methods

Approach:The research topic is developed based on the following approaches: (i) International relations theory approach; (ii) Historical approach; (iii) Systems-structural approach.

Research methodsThe dissertation employs the following research methods: (i) Policy analysis method in international relations; (ii) Case study method; (iii) Analytical-synthetic method, logical-historical method; (iv) Document analysis method; (v) Supplementary methods, such as modeling-generalization, comparison-contrast.

5. Contributions of the thesis

- From a scientific perspectiveThis dissertation studies U.S. policy toward traditional allies in East Asia during the Obama administration (with an in-depth study of South Korea). The interpretations and analyses of U.S. alliance policy with South Korea help clarify the nature and characteristics of U.S. alliance relationships in East Asia. The dissertation can serve as a reference for teaching and scientific research on international relations and U.S. foreign policy.

ButIn practical termsPredicting the impacts of changes and adjustments in US policy towards its East Asian allies on international relations in the region provides useful references for formulating international relations policies by diplomatic and relevant agencies. For Vietnam, studying this issue helps clarify the dynamics of international relations in East Asia in the context of Vietnam's ongoing international integration; understanding the adjustments in the foreign policies of countries in the region such as South Korea and of global powers such as the US, especially understanding the alliance and cooperation goals of these countries to keep pace with regional cooperation and competition trends, and formulating appropriate foreign policies to enhance the effectiveness of strategic partnerships for national and ethnic interests.

6. Structure of the thesis

Besides the Introduction, Conclusion, References, and Appendix, the thesis is divided into 5 chapters:

Chapter 1:Overview of the research situation

Chapter 2:The theoretical and practical basis for implementing the US alliance policy.

Chapter 3:The content and implementation process of the policy toward allies in East Asia by the administration of US President Barack Obama.

Chapter 4:Case Study: U.S. Policy Towards Ally South Korea

Chapter 5:Commentary on US policy toward allies in East Asia during the Obama administration.

CHAPTER 1: OVERVIEW OF THE RESEARCH SITUATION

1.1 Works related to the theoretical issue: the concept of alliance and the US perspective on alliances

1.2 Works related to US policy toward allies during the period 2009-2016

The US alliance policy in general, and with some allies in Asia in particular, has been discussed by scholars both domestically and internationally. However, these studies have mainly focused on assessing and reaffirming traditional alliances in East Asia. There has been no comprehensive and in-depth research on the US-South Korea alliance, especially during President B. Obama's two terms in office.

1.3 Works directly related to the US alliance policy towards South Korea during the period 2009-2016

Reviewing studies from 2009-2016 reveals that analyses of the US alliance policy with South Korea often focused on one area or a few specific policies, lacking comprehensive and holistic assessments. Furthermore, due to time constraints, these studies did not provide a complete overview of the alliance policy with South Korea during both terms of President Obama, failing to clarify the nature of US security and political interests in the region, the dynamics, and the impact of this relationship on international relations in East Asia.

1.4 Comments on the issues that have been resolved and the issues that require further research and resolution.

Overall,one isThese studies have analyzed and clarified several theoretical issues related to the concept of allies and the US perspective on allies; they have also clarified the basis for shaping US policy toward East Asian allies before the period 2009-2016.SecondThis study analyzes the fundamental aspects of the objectives, content, and implementation process of US policy toward its allies in East Asia prior to the period 2009-2016.Third isThis study analyzes the objectives, content, and implementation process of U.S. policy toward South Korea before and during President B. Obama's term, examining each aspect and specific time period.

Key areas for research:(1) Contributing to supplementing the theoretical framework of US policy toward allies to complement in-depth and systematic research on US policy toward allies; (2) Clarifying US policy and specific implementation steps toward East Asian allies (Japan, Philippines, Thailand) in the security and military field during both terms of President B. Obama; (3) In-depth research on US policy toward ally South Korea during the period 2009-2016.

CHAPTER 2: THEORETICAL AND PRACTICAL FOUNDATIONS OF THE IMPLEMENTATION OF THE US ALLIANCE POLICY

2.1 Theoretical basis

2.1.1 The concept of alliance

An "alliance" is a formal commitment between nations to coordinate or support each other in addressing security issues and countering common threats. The ultimate goal of alliances is to share resources and coordinate actions to enhance the standing of allied nations within the international system, increasing their strength compared to non-alliance nations. Whether formal or informal, all forms of alliances consider political and military alliances as their central element.

2.1.2 The concept of alliance from the perspective of Realism and Liberalism

According to Realism, the fundamental purpose of actors in international politics is to protect national interests, primarily ensuring their own maximum security. Therefore, to ensure national security against a country or group of countries that are excessively increasing their power, an alliance is understood as a country signing an agreement with one or more countries with the goal of expanding its national power by using the power of other countries to increase its own power or preventing the power of other countries from increasing that of its rivals. Furthermore, forming alliances is one way to respond to threats to national security.

Based on the principle of emphasizing cooperation between nations, Liberalism introduces the concept of alliances within military alliances, understood as participation in collective security; accordingly, when one country threatens or invades an ally, the remaining countries in the alliance must act collectively to repel that threat.

2.1.3 The US perspective on allies

For the United States, an alliance is the signing of a security treaty between the US and one or more countries to commit to coordinated defense or mutual military assistance to address security issues and counter common threats, especially to the national security of the United States. Above all, the basic objectives defined when the US establishes alliances are: (1) Allies are the foundation for protecting the national security of the United States when the threat extends beyond territorial security. (2) Allies are an important support for the US's position of world hegemony. (3) Allies serve the international relations system established and played a leading role by the US. (4) The US signs alliance treaties to control those allied countries.

2.2 Practical basis

2.2.1 The process by which the US established relationships with traditional allies in East Asia

From factors influencing the need to seek allies in East Asia, such as the threat of communism spreading to the Asia-Pacific region, the weakening of America's close allies in Europe, and the US "containment" strategy requiring support, during the Cold War, the US established alliances with several East Asian countries: Japan (1951), South Korea (1953), the Philippines (1951), and Thailand (1950).

2.2.2 US Policy Towards Allies in East Asia (1945-2008)

Policy toward allies in East Asia during the Cold War (1945-1991)

In fact, the strategic interests of the United States in the Asia-Pacific region were defined around the 1950s. The security cooperation mechanisms between the US and its allies that emerged during this period followed a "hub and spokes" model, where the US was the "hub" and its allies were the "spokes," under US security protection and subject to US policy influence. However, due to differences in national characteristics and the intentions of each country, each cooperation mechanism exhibited its own forms of coordination, operation, and maintenance of the alliance. The US-Japan alliance was primarily a military alliance to facilitate the US military presence in Japan and to contain Japan to the highest degree due to concerns about the resurgence of Japanese militarism; The US-South Korea alliance shares a common stance against North Korea, increasing US influence and completely transforming the political, military, and economic landscape of the country; Thailand and the Philippines are considered by the US as frontline positions to contain nationalist revolutionary movements and communism in Southeast Asia.

Policy toward allies in East Asia after the Cold War

After the Cold War ended and the Soviet Union collapsed, the United States became the sole superpower; however, its overall strength declined relatively. Therefore, during the administration of President Bill Clinton (1993-2000), the US focused on restoring its economic and military strength. While still considering Europe a key strategic area, the US paid more attention to the Asia-Pacific region, including East Asia – a region with many potential instabilities affecting US security interests. Consequently, to ensure national security interests, one of the important solutions implemented by the Clinton administration was to strengthen traditional alliances with Japan, South Korea, Thailand, and the Philippines based on the principle of "shared responsibility."

Policy toward allies in East Asia by the George W. Bush administration (2001-2008)

One of the most striking features of U.S. policy toward its East Asian allies during this period was the fundamental shift in policy objectives following the terrorist attacks of September 11, 2001. At this time, the U.S. promoted a policy of unipolarization within the new world order, increasing comprehensive intervention. Accordingly, the U.S. established an international anti-terrorism coalition led by the U.S., securing the support of close allies. The traditional alliances between the U.S. and East Asian countries were strengthened after the events of September 11, 2001, with a shared understanding of the common threat of terrorism. This served as a new binding force for U.S. security and military alliances in East Asia.

CHAPTER 3: CONTENT AND IMPLEMENTATION PROCESS OF THE BARACK OBAMA ADMINISTRATION'S POLICY TOWARDS ALLIES IN EAST ASIA

3.1 Factors influencing the Obama administration's policy toward allies in East Asia

3.1.1 East Asian Regional Context

The following factors were prominent in East Asia during this period:First,, the increasing importance of the region;second, the powerful rise of China;three isRussia's focus on strengthening relations with Asia aims to bolster its security in the East, compensate for its strategic disadvantages in the West, expand its strategic space, and restore its status as a great power.four isThe security situation in the region is fraught with potential instability and includes hotspots that need to be addressed;year is, the rise of regionalism;six isFollowing the terrorist attacks in the United States on September 11, 2001, countries in the region adjusted their development strategies and policies.

3.1.2 The situation in the United States

Upon assuming power in 2009, President Barack Obama inherited a highly complex legacy from his predecessor. Domestically, the United States faced its biggest financial and economic crisis since World War II, even likened to the "great flood" of 1929-1933. Outside of the United States, the prestige, standing, and image of a superpower were severely diminished on the international stage due to the unipolar, authoritarian foreign policy of the Bush administration, such as: the way it handled the nuclear issues of Iran and North Korea, the recognition of Kosovo's independence from Serbia, and the "export" of American-style democracy and human rights.

3.2 The Obama administration's policy toward East Asia

3.2.1 Overview of President Barack Obama's Foreign Policy

Upon assuming power, President Obama quickly adjusted his strategy and implemented a flexible and adaptable foreign policy to suit the new geostrategic environment, placing greater emphasis on multilateralism and restraint. The goals of this diplomatic strategy were to protect national security, promote economic development and share prosperity both domestically and internationally, and restore America's image and prestige.

3.2.2 The Obama Administration's Policy Towards East Asia

US policy toward East Asia has also undergone adjustments:Regarding strategic objectives...to counter the rise of China—a major threat to U.S. global dominance; and to effectively ensure U.S. security commitments to its East Asian allies.Regarding economic objectives, to support the recovery of the US economy; and to ensure that the economy in the Asia-Pacific region (including East Asia) remains under US influence.Regarding security objectivesMaintaining security and stability in the region is crucial to the security and development of the United States. The North Korean nuclear issue, escalating maritime and territorial disputes, and non-traditional security threats pose new challenges to the US. Therefore, the key elements of the US strategy for East Asia are defined as: Continuing the presence and role of the leading military force in East Asia, especially at military bases in US allies; establishing freedom of navigation for US fleets through alliance treaties; establishing stronger relationships with allies through strategic dialogue; and strengthening existing military and diplomatic dialogue mechanisms with China to avoid unfortunate incidents.

3.3 US Policy Towards Allies in East Asia

3.3.1 Content and main objectives of policy towards allies in East Asia

In order to continue maintaining the US's leading role in the region and ensuring national interests, based on the "rebalancing" strategy in the Asia-Pacific, the policy towards East Asian allies under the Obama administration focused on the goal of military alliances. Specifically: (1) Reshaping and upgrading traditional alliance relationships towards shared interests and common interests; (2) Continuing the military presence in the East Asian region through strengthening and consolidating US agreements with allied countries; (3) Modernizing the US military and the military forces of allied countries. Accordingly, the practical implementation steps towards East Asian allies were carried out at different levels, including reaffirming alliance treaties, moving towards declarations and practical actions to strengthen and expand the alliance; reaffirming the continued use of existing military bases and forces in these countries; Enhancing the supply of modern weapons and equipment, conducting joint exercises to promote the interoperability and coordination of allies in responding to regional security challenges, and being more proactive in handling security hotspots,...

CHAPTER 4: CASE STUDY: US POLICY TOWARDS ITS ALLY SOUTH KOREA

4.1. The foundation of interests, objectives, and content in the US policy toward South Korea.

4.1.1 The benefits for the United States in an alliance with South Korea

South Korea plays a particularly important role in U.S. policy in East Asia. The U.S.-South Korea alliance is seen as the "foundation" for ensuring peace and security on the Korean Peninsula, as the alliance aims to counter the nuclear threat from North Korea; serve as a shield to help the U.S. contain and restrain a rising China that challenges U.S. hegemony in the region; ensure legitimacy for the U.S. presence in the region; and strengthen U.S. economic relations with the region through South Korea as a partner.

4.1.2 Benefits for South Korea in an alliance with the United States

For nearly 60 years, South Korea has centered its worldview around the United States. Some South Korean "interest groups" are reluctant to change their familiar worldview because the alliance with the U.S. helps South Korea avoid being caught in the fierce competition of major regional powers, deter North Korea's nuclear threat, and counter China's growing power. Simultaneously, expanding economic cooperation with the U.S. allows South Korea to tap into the potentially lucrative U.S. market, enhancing its standing and competitiveness in other markets. A close alliance with the U.S. also forms the foundation for developing effective regional diplomacy, supporting the vision of a global South Korea.

4.1.3 Policy Objectives and Content

The Obama administration's goal of strengthening the alliance with South Korea at this time was emphasized as a way to counter North Korea's nuclear program, which the US considered a national security threat that undermined strategic stability in Northeast Asia; and to contain the powerful rise of China, which challenged the US's leadership role in the region.

With these objectives in mind, the Obama administration's policy toward South Korea was implemented with specific measures: continuing to maintain US military forces in South Korea; prioritizing the modernization of weapons and military equipment for South Korea, and promoting the installation of the Terminal High Altitude Area Defense (THAAD) missile defense system; expanding the scale and scope of joint military exercises; implementing the Operational Control of Wartime Command (OPCON) plan for the South Korean military; strengthening political and diplomatic relations with South Korea to achieve consensus on regional issues; and consolidating and upgrading the US-South Korea global strategic alliance.

4.2 Policy Implementation Process during the period 2009 - 2016

During this period, the United States and South Korea adopted the 2009 Alliance Vision, agreeing to closely coordinate efforts to address regional challenges. Subsequently, the U.S. intensified new strategic directions, elevating its alliance with South Korea to a "global strategic alliance." Specifically, the U.S. achieved South Korea's consensus on policy regarding North Korea's nuclear program based on a policy of "strategic patience"; increased its military presence in South Korea to deter North Korea and China; commenced the transfer of OPCON to the South Korean military; installed the THAAD system; successfully signed the KORUS FTA, opening opportunities for economic and trade cooperation and further strengthening the U.S.-South Korea alliance; and shared common values ​​such as democracy, an open society, and human rights.

CHAPTER 5: REMARKS ON US POLICY TOWARDS ALLIES IN EAST ASIA DURING THE OBAMA ADMINISTRATION (2009-2016)

5.1 Commentary on US policy toward allies in East Asia during the Obama administration

5.1.1. Results

Throughout his two terms in office (2009-2016), President Obama's administration adopted a proactive approach to policy towards East Asian allies and achieved notable results, including: renewing and restructuring relations with East Asian allies, expanding the alliance's scope from regional to global; reaffirming the commitment to regional security and protecting allies under signed mutual defense treaties; and strengthening relations with existing US allies during this period, which significantly contributed to consolidating the US position in the region and the world.

5.1.2 Limitations

However, limitations remain due to uncertainty about the sustainability and depth of U.S. security commitments. U.S. policy toward its allies seems to have failed to reassure them, demonstrating a lack of strong commitment. Furthermore, there is an erosion of the U.S.'s credibility as the "security umbrella" that allies relied upon to protect their national security against regional threats, as the U.S. has been unable to provide a clear strategy, weakening its ability to effectively deter adversaries. This is especially true given its failure to prevent the rise of China in the region and its inability to effectively contain North Korea's nuclear threat.

5.2 Commentary on US policy toward its ally South Korea during the Obama administration

5.2.1 Results and limitations of the US alliance policy towards South Korea under the Obama administration

The US-South Korea alliance between 2009 and 2016 is considered one of the best periods in the two countries' history. This relationship was upgraded to a "global strategic alliance," with the US achieving several goals, including the completion of the THAAD system in South Korea and the successful signing of the KORUS FTA. However, alongside these achievements, the US still had political disagreements with South Korea on several regional issues, such as US policy towards China and the US approach to the six-party talks on North Korea's nuclear program.

5.2.2 Characteristics of the US alliance policy toward South Korea under the Obama administration (compared with Japan and the Philippines)

Based on the case study of South Korea, several common characteristics can be observed in US policy towards its East Asian allies during this period: Up until the Obama administration, US policy towards its allies continued to strongly commit to protecting them from regional security threats. Allied countries continued to serve as a "pillar" supporting the US in maintaining its leadership role in the region and controlling threats to US security. The nature of alliance relationships during this period underwent a qualitative change; the "asymmetrical" characteristic was gradually adjusted, shifting from a one-sided US leadership to mutual support, and from one-sided US leadership to bilateral, equal cooperation. The position and role of allied countries continued to be affirmed and expanded, elevating their importance in US foreign policy in East Asia.

5.3 Adjustments to policies toward allies in East Asia during the Donald Trump administration

5.3.1 Adjustments to policies toward allies in East Asia in general

One of the main tenets of the previous administration's "rebalancing" policy in the Asia-Pacific, continued under President D. Trump, was strengthening traditional bilateral alliances; containing the military power of regional powers, especially China, through these traditional close military alliances. In the "Free and Open Indo-Pacific" strategy, the Trump administration continued to emphasize the role of the US alliance system in the region, highlighting the role of Japan, an ally that has fought alongside the US in every conflict; South Korea, with its alliance and friendship forged through many historical challenges; and the Philippines and Thailand, important allies and markets for the US.

With the goal of "America First," the Trump administration's policy toward allies has undergone significant adjustments. The objectives of US policy toward allies are clearly defined: US alliances continue to provide a US presence in the region; and alliances are strengthened and developed into an extensive network capable of deterrence and decisive action to address common global challenges. In practice, the Trump administration adjusted its policy toward allies in the security and military spheres toward a tougher stance, demanding greater shared responsibility from allies for national, regional, and global issues.

5.3.2 Adjustments to policy toward ally South Korea

Regarding the U.S.-South Korea alliance, President D. Trump reaffirmed that it is a crucial alliance essential for securing U.S. economic and security interests, and for peace, security, and prosperity in the Indo-Pacific region. This relationship is built on shared principles of democracy, human rights, and the rule of law. Accordingly, the goal of the Trump administration's strategy toward South Korea remains to achieve denuclearization and comprehensive control of North Korea's nuclear weapons and ballistic missiles, establishing lasting peace on the Korean Peninsula. The U.S. remains committed to defending South Korea through robust defense support and enhanced security guarantees based on the U.S.-South Korea Mutual Defense Treaty. The Trump administration emphasizes the implementation of an expanded deterrence strategy toward South Korea based on the full U.S. military capabilities, both conventional and nuclear. In fact, the Trump administration agreed with South Korea on the North Korean nuclear issue, actively pushed for the swift transfer of OPCON to the South Korean military, maintained a US military presence, modernized the South Korean military, renegotiated the KORUS FTA, and strengthened South Korea's role in global affairs, among other things.

CONCLUDE

From the analysis of "US Policy toward East Asian Allies during the Obama Administration - The Case of South Korea," the following conclusions can be drawn:

The firstThe post-Cold War world witnessed tremendous changes in the global and Asia-Pacific regional landscape, especially the shift in the focus of security and economics from West to East, and from Europe to Asia. Despite being relatively weakened by the post-Cold War effects, the United States maintained its role as a superpower in a multipolar world, continuing its ambition for global hegemony. Therefore, the US administration repeatedly changed its global security strategy, from the "expansion commitment" of the Bill Clinton administration, the "preemptive strike" against global terrorism of the George W. Bush administration, to the "rebalancing" and "pivot" to Asia-Pacific policies of President B. Obama. All of these demonstrate a trend of shifting US attention to the Asia-Pacific region, particularly under the Obama administration.

In fact, the Asia-Pacific region has always held a crucial position in the U.S. global strategy. However, the focus has shifted over time. Under President Barack Obama, the U.S. perceived the Asia-Pacific as a geostrategic region, encompassing both economic opportunities and significant security challenges for the U.S. It is in this region that both immediate and long-term security challenges have emerged, requiring the U.S. to focus its efforts on addressing them.Above all, the Asia-Pacific region is the focal point of America's regional and global power competition.One of the strategic priorities here is containing the rise of China. China is considered both an adversary and a partner of the United States. During the period when the US left its role vacant in the Asia-Pacific, China took advantage of the situation to rise to become a major power with both economic and military influence in the region. China moved towards dominating economic and trade relations, consolidating its military strength, and demonstrating a blatant and unilateral approach in handling security disputes with countries in the region, especially in the South China Sea and East China Sea, leading to intense power competition with the US. In addition, the great power competition in the region must take into account the role of Russia in its eastward-looking policy. Russia wants to restore its image as a great power in the world, and therefore cannot ignore the Asia-Pacific region, which it maintains through the provision of military and defense capabilities as well as economic trade.

In the Asia-Pacific region, East Asia has emerged as a area of ​​particular concern to the United States due to the serious security challenges it faces.Northeast Asia is plagued by the security instability of the Korean Peninsula due to the increased nuclear threat from North Korea. Southeast Asia is a target for global extremist terrorist forces. Furthermore, both regions witness intense territorial conflicts in the East China Sea and the South China Sea between regional countries, particularly the display of military power by China.

Therefore, during his term, President B. Obama actively implemented the "rebalancing" policy in the Asia-Pacific, especially the "re-presence" in East Asia, in order to maintain America's role and influence in the region, prevent any rival from surpassing the US, and ensure national security and American interests there.

MondayIn the "rebalancing" strategy for the Asia-Pacific, the security and military sector was considered the most actively implemented area under the Obama administration. With this priority, the most important aspect was the Obama administration's focus on establishing a strong presence in the region by renewing and upgrading traditional alliance relationships. Based on shared strategic values ​​and interests, America's traditional allies in the region are key to America's return to the region, maintaining its presence, participation, and leadership role. Bilateral security commitments between the US and its allies both safeguard America's strategic interests in the region and strengthen a robust security network for the US in addressing regional security challenges. This is how the US exercises "smart power," meaning that the US cannot continue to act alone in addressing security challenges but needs the cooperation of many nations, strengthening interconnected networks to create a timely source of power.

During this period, the Obama administration set the goal of strengthening and enhancing the power of US alliances in the region to coordinate responses to traditional and non-traditional security threats and challenges in the 21st century. The US identified key allies in the region with whom it needed to strengthen and modernize its relationships, including Japan, South Korea, the Philippines, and Thailand. The US's implementation focused on the following objectives: reaffirming its commitment to defense and security, expanding the scope of alliances at the regional and global levels, enhancing operational capabilities and coordinated action, and sharing responsibility in regional issues. Achievements during President Obama's term included agreements to upgrade and expand alliance relationships with countries such as Japan and the Philippines; redeploying US military forces; and reaching agreements with allies on a continuous or rotational presence in the region (Japan, the Philippines). Providing advanced weapons and equipment to enhance the defense capabilities of allied countries (Japan, the Philippines, and Thailand); and continuing to conduct joint exercises with allied forces (Japan, the Philippines, and Thailand). Although limitations remain in the implementation of policies toward East Asian allies due to differences in political views on some regional issues, the Obama administration continues to achieve consensus and support from allies to varying degrees, assisting the US in addressing factors challenging US security in the region.

TuesdayAmong the US's bilateral alliances in East Asia, South Korea is considered a quintessential and loyal ally. Stemming from the security protection under the US "nuclear umbrella" since the Cold War, the US-South Korea alliance from 2009-2016 is considered one of its best periods. Recognizing South Korea's increasingly prominent role in coordinating actions with the US on regional and global issues, the Obama administration decided to upgrade the US-South Korea alliance to a "global strategic alliance." This means the US is demanding that South Korea share more responsibility, stand alongside the US in resolving conflicts not only regionally but also globally, on traditional and non-traditional security issues; continue to spread American-style democratic ideology; and actively participate extensively in regional and global trade value chains. In particular, the Obama administration continued to affirm South Korea's importance as an ally supporting security on the Korean Peninsula, countering the growing threat from North Korea's nuclear program, creating a deterrent shield against both North Korea and China, and containing Japan. The results include the elevation of the US-South Korea global strategic alliance, the successful signing of the KORUS FTA, and the final phase of the THAAD system construction in South Korea. In addition, there has been a strong deployment of US military forces at military bases in South Korea, the provision of modern weapons and equipment, the upgrading and modernization of joint military exercises, initial positive results in bilateral trade, and the effective maintenance of American democratic and human rights values. Thus, the US alliance policy towards South Korea achieved positive results during President B. Obama's term, despite some limitations (such as the continued increase in North Korea's missile and nuclear tests; the incomplete transfer of wartime authority to the South Korean military; and the emergence of conflicts between China and South Korea due to US policies towards the latter, etc.).

WednesdayWith the advent of President Donald Trump's administration and his "Free and Open Indo-Pacific" strategy, the role of East Asian allies has continued to be affirmed, strengthened, and developed. President Trump's policy towards allies demonstrates continuity while also showing changes compared to the previous administration. In the second decade of the 21st century, the Obama administration reaffirmed that East Asian allies serve as an effective "defense system" in the region, helping the US maintain regional security, especially given China's increasingly assertive stance on regional issues and North Korea's persistent nuclear weapons ambitions. Therefore, in the context of these serious security threats to the national security of the US and its allies, the Trump administration cannot ignore the role of East Asian allies. Furthermore, the overarching goal of the United States is to maintain its leadership role and stabilize regional security; therefore, the US continues to act to reaffirm its security commitment to its allies through forward-looking operations. Despite adjustments by the Trump administration to demand greater responsibility sharing from allies, Japan, South Korea, the Philippines, and Thailand remain essential factors in ensuring regional security and strengthening US influence in the region amidst increasing competition among major powers both within and outside the region.

In short, throughout the history of the formation of US alliances in East Asia, spanning the presidencies of post-Cold War eras, particularly the alliance policy of President B. Obama's administration, compared with adjustments under President D. Trump, it is clear that the US prioritizes the Asia-Pacific region, now expanded to the Indo-Pacific, and in particular, its policy towards traditional allies has undergone adjustments reflecting flexibility and pragmatism in US foreign policy in general.