Thailand-Cambodia Border Dispute: How does U.S. and Chinese intervention in peace-keeping efforts speak to the influence of global hegemons over smaller states?

By: Karen Liu 

Editor: Anna Pringle 

Editor-in-Chief: Grace Samuel 

The views expressed are the author's own and do not reflect the views of the International Relations Society. 

Image credit: “Aranyaprathet - Poipet Border” by Thanate Tan, CC BY 2.0 

The inherent power dynamic embedded within the relationship between global hegemonic states and smaller states is a factor that will undoubtedly affect the course of the peace-making process for regional conflicts. This phenomenon is observed through the recent border conflict between neighbouring Southeast Asian countries: Thailand and Cambodia. The recent violent escalation resulted in a series of violent clashes that raged on for five days, beginning on July 23^rd, 2025.  

Tensions between the two states have existed for decades, stemming from the ambiguous boundaries drawn by French colonials who previously occupied Cambodia and the independent Siam state. This is further perpetuated by issues such as ethnic overlaps and land disputes that housed significant temples. Recent developments could also be attributed to contemporary domestic political problems in Thailand, specifically the manoeuvrings of the elite to side-line civilian political figures in a period of political discourse between the old, established power structures and an emerging, highly discontent population of youth and the working class. Both the United States and China have been largely involved in the peace-making process following these recent developments in the regional conflict. Senior officials from both nations were in attendance at the ASEAN meeting held on 28 July 2025, which aimed to broker a ceasefire between Thailand and Cambodia. Both the United States and China have also been entangled in various relationships, militarily and diplomatically, with the states in conflict, formally extending from the last century to present day.  

Relationships with the U.S. and China 

A relationship with the U.S. and China extends to both Southeast Asian countries, each varying in degrees of cooperation. U.S. and Thailand have formed long-standing bilateral relations, with Thailand as a key non-NATO ally especially in areas such as defence and commerce. Both countries have a strong strategic partnership particularly in matters of security in the form of military equipment, joint-training exercises and the construction and improvement of infrastructure. However, in the last decade, these ties have been strained by the developments of Thailand’s strengthening relations with China and the military coups of 2006 and 2014. China’s influence, particularly over major Myanmar ethnic armed groups and its political and economic footprint within Thailand, is a pressing point of consideration for Bangkok. It has risen to the extent where Bangkok must consider Cambodia’s steps towards military modernisation and the recent intensification of the border dispute, under the context of China’s prominent security role in the region. Hence, with the growing gaps in the relationship between the U.S. and Thailand and China’s involvement with their neighbours, ties between China and Thailand have grown as a result.  

In contrast to Thailand’s approach, Cambodia largely leverages its relationship with China to propel its military on to a path of modernisation. This includes the acquisition of advanced military technology such as naval assets and rocket launchers systems, as well as an upgrade to its naval bases such as the Ream Naval Base, efforts that are mainly motivated by the need to increase security measures against its neighbours: Thailand and Vietnam.Nonetheless, to avoid solely relying on China, Cambodia occasionally reaches out to the U.S, especially noted in the latest series of events with Thailand, as well as U.S. president Donald Trump’s involvement in the subsequent ceasefire arrangements 

Implications of Hegemonic Intervention 

The entanglement of major global powers of the United States and China in the various operations of smaller states, reflect their undeniable influence, regardless of the scale of the issue. Not only do smaller states depend on hegemonic states in a myriad of sectors such as markets, security and diplomatic cover, these hegemons shape the definition of peace even when a conflict has no direct correlation with these larger states. As evidenced by the recent phase of the border dispute between Thailand and Cambodia, heavy U.S. involvement in the peace-making process delineates Washington’s efforts in framing its reputation as both a responsible crisis manager and an agent of democracy. However, this mere facade as a neutral mediator masks their true agenda that prioritises alliance management and its military position in Southeast Asia. In the same interest of protecting one’s own interests, Chinese intervention in the dispute aims to prevent instability near its borders and western domination of regional conflict mediation frameworks, to ensure the protection of the Belt and Road initiative and the Mekong economic corridors. Although the U.S. and China are both united by the hegemonic ability of quick peace-making through intervention, this phenomenon can potentially result in entrenching dependency and limiting the policy autonomy of smaller states, as both Thailand and Cambodia must calculate their actions to the U.S. and China’s reactions accordingly. Ultimately, this regional border dispute delineates how global hegemonic intervention inevitably penetrates the peace-making process. This is due to their structural power and the prioritisation of their strategic interests, thus not only defining if and when the conflict stops, but also criteria for peace based on their own terms.