The use of force in bien dong (south china sea) under the light of international law = việc sử dụng vũ lực trên biển đông dưới góc độ luật quốc tế

VIETNAM NATIONAL UNIVERSITY, HANOISCHOOL OF LAW TRAN THI KIM NGUYEN THE USE OF FORCE IN BIEN DONG SOUTH CHINA SEA UNDER THE LIGHT OF INTERNATIONAL LAW Major: The Law of the Sea and Marit

VIETNAM NATIONAL UNIVERSITY, HANOI

SCHOOL OF LAW

TRAN THI KIM NGUYEN

THE USE OF FORCE IN BIEN DONG (SOUTH CHINA SEA) UNDER THE LIGHT OF INTERNATIONAL LAW

MASTER’S THESIS

Hanoi - 2020

VIETNAM NATIONAL UNIVERSITY, HANOI

SCHOOL OF LAW

TRAN THI KIM NGUYEN

THE USE OF FORCE IN BIEN DONG (SOUTH CHINA SEA) UNDER THE LIGHT OF INTERNATIONAL LAW

Major: The Law of the Sea and Maritime Management

Code: 8380101.08

MASTER’S THESIS

Supervisor: Associate Professor Nguyen Hong Thao

Hanoi – 2020

This is to declare that this Thesis with the title “The use of force in Bien

Dong (South China Sea) under the light of international law” is conducted by

myself under the supervision of Associate Professor Nguyen Hong Thao, infulfilment of the requirement for the Master of Law Degree at School of Law,Vietnam National University (Hanoi) The data and the research conclusionspresented in this Thesis are done with the most sincere of mine

I am entirely responsible for this undertaking

Postgraduate student,

Tran Thi Kim Nguyen

TABLE OF CONTENTS

ABBREVIATIONS AND FIGURE

INTRODUCTION 1

CHAPTER 1: THE CONCEPTS AND LEGAL FRAMEWORK GOVERNING THE THREAT OR USE OF FORCE IN BIEN DONG 13

1.1 The concept of the threat or use of force at sea 13

1.1.1 The threat or use of force in international relations 13

1.1.2 The threat or use of force at sea 17

1.2 The set of rules governing the threat or use of force at sea 22

1.2.1 General principles and provision of public international law 22

1.2.2 Law of the sea 29

1.2.3 International maritime law 33

1.2.4 International law on armed conflicts at sea 34

1.2.5 Regional agreements relating to the threat or use of force in Bien Dong 39

1.3 The precedents and opinions concerning the use of force at sea 45

CONCLUDING REMARKS OF CHAPTER 1 53

CHAPTER 2: THE PRACTICE OF THE USE OF FORCE IN BIEN DONG 55

2.1 Typical incidents involving the use of force in Bien Dong 55

2.2 Coercive intent in China’s activities in Bien Dong 60

2.3 Grey zone conflicts 63

CONCLUDING REMARKS OF CHAPTER 2 69

CHAPTER 3: PROSPECT OF PEACE AND SECURITY IN BIEN DONG 70

3.1 Suggested contents in the COC or equivalent documents 70

3.2 The possibility of using judicial organs 81

CONCLUDING REMARKS OF CHAPTER 3 85

CONCLUSIONS 87

BIBLIOGRAPHY 89

ABBREVIATIONS AND FIGURE

Convention on the International Regulations forPreventing Collisions at Sea

Center for Strategic and International StudiesCode for Unplanned Encounters at SeaInternational Court of Justice

International Committee of the Red CrossInternational Law Commission

United NationsUnited Nations Convention on the Law of the seaUnited States

Figure 2.1: China’s claim and selected Grey Zone incidents

in Bien Dong

1 The necessity of the research

In Bien Dong, China has been threatening and using force in both direct andindirect manners On the one hand, a vast array of activities gradually militarisingthis area has been conducted in order to strengthen and expand China’s ambition orillegal claims on sovereignty, sovereign rights and jurisdiction at sea In particular,China has been conducting land reclamation and construction on its illegallyoccupied seven maritime features in the Spratly Islands, establishing military bases

to control the entire region progressively

On the other hand, China has well-taken advantages of grey zone conflicts to

coerce or violation the non-use of force principle with the fail accompli strategy,

which raises the risk of war for every state operating in Bien Dong on facingChina’s ambition

In that context of Bien Dong, Vietnam is directly and deeply affected by theuse or threat of force of Chinese operations The fundamental rights and coreinterests of Vietnam relating to sovereignty, sovereign rights and jurisdiction overgeographical entities in Paracel and Spratly Islands and maritime zones inaccordance with international law (especially United Nations Convention on theLaw of the Sea 1982) were severely violated Especially, in July 2019, theaggressive activities of China in Vanguard Bank can be considered as a newescalation in incursion the legitimate maritime zones of Vietnam

Therefore, the study about the principles and provision of international lawrelating to the use or threat of force at sea were extraordinarily essential to identifythe legal framework as well as to limit or eliminate the risk of threatening peace andsecurity from Chinese activities in Bien Dong

Because of those reasons above, I am dedicated to the topic "The use of force

in Bien Dong (South China Sea) under the light of international law" and conduct

my Master's thesis on this issue

2 Literature review

(i) The concepts of the threat or use of force at sea

As a classical matter of international law, the concepts of the use or threat offorce has been studied profoundly However, the vast majority of previous works onthis topic focus on the force occurring on land Consequently, there remain severalopen and controversial questions relating to the use or threat of force at sea

In terms of the notion of the use or threat of force in international relations,the textbooks of Public International Law written by Ho Chi Minh City University

of Law (Tran Thi Thuy Duong and Tran Thang Long, 2013), School of Law Vietnam National University (Nguyen Ba Dien, 2013), Ngo Huu Phuoc (2013), …provide an overview of the notion By approaching these concepts with thedistinctive purposes of this Thesis, these contents are the very starting point forfurther research about the concepts of the use or threat of force

-This Thesis pays much attention to the studies of Constantinos Yiallourides(2018), especially “Is China Using Force or Coercion in the South China Sea? Why

words matter” - an article on The Diplomat, and The Use of Force in relation to

Sovereignty Disputes over Land Territory – a product of the British Institute of

International and Comparative Law (BIICL) These two works contribute moredetails about the concept of the use or threat of force in international relations andnotes for the maritime domain

Furthermore, René Värk (2013) with the paper “The Legal Framework of theUse of Armed Force Revisited” in Baltic Security & Defence Review analyses morethoroughly about the threat of force, which becomes the foundation for referring thethreat of force at sea

Besides, David H Anderson (2013) in “Some Aspects of the Use of Force in

Maritime Law Enforcement” from book International courts and the development

of international law: Essays in honour of Tullio Treves also addresses more specific

characteristics when using force at sea Nonetheless, the use of force analysed inthis work is the force in maritime law enforcement, which falls outside the scope ofthis Thesis.

Notably, Jinxing Ma and Shiyan Sun (2016) with the paper “Restrictions on

the use of force at sea: An environmental protection perspective” in War and

security at sea - International Review of the Red Cross shows the thinking of

Chinese scholars about the use of force at sea However, this research is aiming forthe environmental protection perspective and little has been said about the legalbasis of the use of force

This Thesis learns a lot from Patricia Jimenez Kwast (2008) with the paper

“Maritime Law Enforcement and the Use of Force: Reflections on theCategorisation of Forcible Action at Sea in the Light of the Guyana/ SurinameAward” in Journal of Conflict and Security Law Regarding the term of the threat oruse of force at sea, this paper presents a practical approach from the Guyana/Suriname Award Moreover, Kwast analyses explicitly the distinction betweenmaritime law enforcement and the use of force in international relations in theory

Concerning distinction between maritime law enforcement and the use offorce that violates the international principles, it is indispensable to credit WolffHeintschel von Heinegg (2016) with the article “The difficulties of conflictclassification at sea: Distinguishing incidents at sea from hostilities” in War andsecurity at sea - International Review of the Red Cross (2016) Heinegg gives aprofound analysis of distinguishing incidents at sea from armed conflicts at sea

(ii) Set of rules governing the threat or use of force at sea

This Thesis has not approached any works on this field with an adequatelegal basis The materials are collected by three criteria: (1) Legal frameworkregulating the threat or use of force in international law, (2) The applicable law to

the maritime domain and (3) regional treaties concerning the threat or use of force

with the article “The Legal Framework of the Use of Armed Force Revisited” inBaltic Security & Defence Review, Katie Peters (2004) with the article

“International Law and the Use of Force” in Queensland University of TechnologyLaw and Justice Journal, …

Those research works provide fundamental knowledge of the threat or use offorce in international law Nonetheless, they primarily focus on the force exercising

on land but not at sea This Thesis develops the contents that are in commonbetween the two domains (land and sea) with the distinctive characteristics of themaritime domain

It is generally agreed that the ILC’s document has significantly contributed tothe development of international law Some reports address further analysis of thelegal framework governing the threat or use of force in international law such as

Commentaries on Draft articles on Responsibility of States for Internationally Wrongful Acts, Dire Tladi (2019) with the draft conclusions and draft annex

provisionally adopted by the Drafting Committee on first reading “Peremptorynorms of general international law (jus cogens)”; Claudio Grossman Guiloff (2019)with the Statement of the Chair of the Drafting Committee on “Peremptory norms ofgeneral international law (jus cogens)”

These ILC’s documents enhance understanding of the author of this Thesisabout the non-use of force principle in international law in order to distinguish theprohibition of aggression and the lawful use of force properly

Remarkably, the ICRC Commentaries and the International Review aboutWar and security at sea with a series of articles on the armed conflicts at sea areessential, most relevantly:

Bruno Demeyere, Jean-Marie Henckaerts, Heleen Hiemstra and EllenNohle (2016), "The updated ICRC Commentary on the Second GenevaConvention: Demystifying the law of armed conflict at sea";

W Heintschel von Heinegg (2016), “The difficulties of conflictclassification at sea: Distinguishing incidents at sea from hostilities”;Vincent Bernard (2016), “War and security at sea: warning shots”;

Steven Haines (2016), “War at sea: Nineteenth-century laws for first-century wars?”

twenty-In addition, this Thesis also learns from the presentations of Trang Ngo and

Asian Session on International Humanitarian Law, Hanoi, Vietnam, 24-28 June

2019 co-organised by the Diplomatic Academy of Vietnam and the ICRC

Those articles and presentations provide a variety of specific and practicalaspects about naval warfare, which supports this Thesis to analyse precisely whathappens at sea in each situation of violence and the risk of hostilities of aggressivemaritime activities

Once again, Patricia Jimenez Kwast (2008) with the article “Maritime LawEnforcement and the Use of Force: Reflections on the Categorisation of ForcibleAction at Sea in the Light of the Guyana/ Suriname Award” in Journal of Conflictand Security Law is important for this Thesis to indicate the blurred a line betweenmaritime law enforcement and the use of force

Notably, there is a Master’s thesis major in Law of the Sea from Faculty ofLaw – The Arctic University of Norway of Sarah Goyette (2014) with the title

“Threat or Use of Force at Sea - Assessing the Adequacy of the Convention on theLaw of the Sea” This Thesis learns from this “counterpart” the interpretation ofArticle 301 UNCLOS 1982 and its approach the matter of the threat or use of forcefrom the law of the sea.

Besides, this Thesis also acknowledges Jonathan G Odom (2018) with thestudy “Guerrillas in the Sea Mist: China’s Maritime Militia and International Law”

in Asia-Pacific Journal of Ocean Law and Policy This study offers a paramountguideline to clarify the Chinese maritime militia under the light of international law

(iii) The practice of the use of force in Bien Dong

Tension in Bien Dong has been received much concern of scholars Thematter of the threat and use of force deployed by China’s maritime forces hasbecome the topic or a part of the topic of a variety of scientific works

This Thesis uses selectively the list of incidents provided by Van Pham(2016) with the study “The Use or Threat of Force in the South China Sea DisputesSince 1945: A Timeline”, which is a product of the South China Sea Chronicle Thisstudy includes a wide range of activities in its timeline from 1945-2011: Exchange

of fire between governmental agencies of two states; Opening fire by governmentalagencies of one state against governmental or civilian vessels of another state;Activities such as blockage, ramming, sinking, water cannon firing, dousing ,taken by governmental armed vessels of one state against governmental or civilianvessels of another state; Other activities of confrontational nature involving armedforces of states Nonetheless, not all of those activities are under the scope of thisThesis Additionally, this Thesis also examines numerous incidents after 2011

Significantly, Constantinos Yiallourides (2018) has two papers relevant to thisissue, namely: “Force and coercion in the South China Sea: Why does it matter inInternational Law?” - presentation paper in the 10th South China Sea international

conference: Cooperation for regional security and development, November 08-09,

2018 in Da Nang City; and “Is China Using Force or Coercion in the South ChinaSea? Why words matter” in The Diplomat This Thesis can learn from the two how

to assess China’s activities in Bien Dong under international law

Besides, there exist numerous works on examining China’s activities in BienDong, such as: Demetri Sevastopulo and Kathrin Hille (2019) with the paper “USwarns China on aggressive acts by fishing boats and coast guard” in The FinancialTimes, Abhijit Singh (2018) with the paper “Between War and Peace: Grey-ZoneOperations in Asia” – a product of Australian Institute of International Affairs, ĐỗThanh Hải (2011) with the paper “In retrospect of China’s policy toward SouthChina Sea disputes since 2007” in International Studies, Kenneth E Bauzon (1980)with the paper “China and the use of force in international relations” in AsianThought & Society, … Those studies raise the question of the grey zone conflict andhow China takes advantages from this

More importantly, there are two studies on China’s maritime militia, namelyRobert McLaughlin (2019) with the paper “The Legal Status and Characterisation ofMaritime Militia Vessels” in Blog of the European Journal of International Law;and one more time, Jonathan G Odom (2018) with the paper “Guerrillas in the SeaMist: China’s Maritime Militia and International Law” in Asia-Pacific Journal ofOcean Law and Policy These two papers present an analysis of China’s maritimemilitia under international law and suggest some initial solutions

Recently, Andrew S Erickson and Ryan D Martinson (March 15, 2019) has

published the book China's Maritime Gray Zone Operations With contributions

from some of the world's leading subject matter experts, this book aims to close thatgap by explaining the forces and doctrines driving China's paranaval expansion,operating in the grey zone between war and peace The book covers China's majormaritime forces beyond core grey-hulled Navy units, with particular focus onChina's second and third sea forces: the "white-hulled" Coast Guard and "blue-

hulled" Maritime Militia Increasingly, these paranaval forces, and the grey zone inwhich they typically operate, are on the frontlines of China's seaward expansion.However, this Thesis does not have an opportunity to access the book Figure 2.1 ofthis Thesis is taken from the online pages for introduction.

(iv) Solutions for Vietnam

There are a limited number of works on solutions for Vietnam in the context

of China’s aggressive activities in Bien Dong

Nguyen Hong Thao with numerous eminent works provides Vietnam’sposition of the disputes in Bien Dong, for example, “Vietnam's Position on theSovereignty over the Paracels & the Spratlys: Its Maritime Claim”, Journal of EastAsia International Law, V JEAIL (1) 2012

Significantly, Nguyen Viet Long (2012) with the book Lẽ phải: Luật quốc tế

và chủ quyền trên hai quần đảo Hoàng Sa và Trường Sa (International law and sovereignty over the Hoang Sa and Truong Sa archipelagos) presents reasonable

solutions to resolve all disputes in the direction of respecting sovereignty, sovereignrights and jurisdiction of the parties in Bien Dong, keeping peace and security forthe whole region

Moreover, this Thesis is of the same mind with the recommendations ofNguyen Hong Thao and Ton Nu Thanh Binh (2019) in Maritime Awareness Projectentitled “Maritime Militias in the South China Sea – 2” Accordingly, the maritimemilitias operating in Bien Dong should be regulated in COC and adhered to theCUES

Constantinos Yiallourides (2018) with the paper “Is China Using Force orCoercion in the South China Sea? Why words matter” in The Diplomat offers some

ideas relating to erga omnes obligation in international law.

Besides, Đặng Duân (2019) with the paper “Đã đến lúc hình thành liên minhtuần duyên Biển Đông (It is time to form the coast guard alliance in Bien Dong)”

suggests the idea of establishing the joint coast guard in Bien Dong with theparticipation of other powers like the US, Japan, Australia, … to balance with Chinapower.

Another way, Irini Papanicolopulu with the paper “Enforcement action incontested waters: the legal regime” supports the idea of initiating the case to thejudicial organs However, Papanicolopulu does not refer to the context of BienDong

From diplomatic approach, Jonathan G Odom (2018) with the paper

“Guerrillas in the Sea Mist: China’s Maritime Militia and International Law” inAsia-Pacific Journal of Ocean Law and Policy advises that the issues should bedebated further in international conferences Additionally, Le Hong Hiep (2019)

with the paper “Vietnam’s Position on the South China Sea Code of Conduct”

-ISEAS Perspective 22/2019 indicates directly the expect of Vietnam for the SouthChina Sea Code of Conduct

3 The purpose, objectives and the scope of the research

The purpose of the research

This Thesis is aiming for assessing the matter of the threat or use of force inBien Dong under international law

The objectives of the research

In order to fulfil the above-mentioned purpose, this Thesis sets out fourobjectives:

First, clarifying the concept of the threat or use of force at sea;

Second, analyzing the legal framework governing the threat or use of force in

Bien Dong;

Third, refering to the pratice in Bien Dong;

Fourth, proposing solutions for Vietnam.

The scope of the research

Regarding the limit of the content: This Thesis concentrates on studying theuse or threat of force in international relations occurred in the maritime domain; thereferences to other forms of force such as law enforcement is for illustration only

Regarding the limit of space: The central concern of this Thesis is withinBien Dong

Regarding the limit of time: The incidents relating to use or threat of force inBien Dong were collected and systemized from 1945 to the time completing thisThesis (July 2019)

4 The novelty and contribution of the research

In theory, this Thesis clarifies the concept and characteristics of the use orthreat of force at sea Additionally, this Thesis also points out the legal frameworkgoverning this matter

In practice, this Thesis examines the typical incidents relating to use or threat

of force in Bien Dong from 1945 to 2019 and proposes solutions for Vietnam fromthe author’s perspective

6 The methods of the research

This Thesis uses a combination of different research methods, namely:

Methodology

The Thesis is based on the methodology of dialectical historical materialism

of Marxism-Leninism

Social scientific research methods

the Thesis, for example, the concept and characteristics of the use or threat of force

at sea and the legal framework governing this matter and the practice of the threat

or use of force in Bien Dong

similarities or differences between legal provisions regulating the use or threat of

force at sea and to weigh the gravity of “force” happening at sea

the systematisation of the incidents of using force or the threat of using the force of China

in Bien Dong

other fields of studies beyond personal specialisation such as military or defence science,the law on armed conflicts, etc

Writing methods

This Thesis incorporates the use of many methods of argument to writeclearly and to ensure the fluency and coherence such as the deductive and inductivemethods

7 Structure of the Thesis

The Thesis is divided into three chapters:

Chapter 1 with the title “the concepts and legal framework governing thethreat or use of force in Bien Dong” presents the concept of the threat or use offorce at sea through the notion of the threat or use of force in international relations.Then, the set of rules governing the threat or use of force at sea would be figuredout, including: General principles and provision of public international law, law ofthe sea, International maritime law, International law on armed conflicts at sea;Regional agreements relating to the threat or use of force in Bien Dong Next, theprecedents and opinions concerning the use of force at sea would also be examined

Chapter 2 with the title “the practice of the use of force in Bien Dong” wouldsystemise the typical incidents involving the use of force in Bien Dong and thenanalyses “Fait accompli” strategy and grey zone conflict.

From the results of the two previous chapters, chapter 3 suggests potentialsolutions for Vietnam, including: (1) potential content of COC concerningminimising or eliminating the threat or use of force in Bien Dong and (2) thepossibility of using the judicial settlements of disputes concerning the threat or use

of force in Bien Dong

8 The publications of the author relating to this Thesis

Tran Thi Kim Nguyen, Vo Thi Thanh Nguyen and Le Thi Xuan Phuong(2016), “International law on military operations at sea and reality in the SouthChina Sea”, scientific works at “Student Research Award” in 2016 (in Vietnamese);

Tran Thi Kim Nguyen (2018), “The issue of use of force from Chinese armedforces on the South China Sea in the light of international law of the sea”,presentation paper in the International Conference “The recent development ofInternational law of the sea – from the viewpoint of the international and Vietnam”,

Besides inheriting the results of research works as mentioned in LiteratureReview, the contents done in the personal previous research about militaryactivities, maritime security and the legal basis of China's maritime operations inBien Dong will also be developed in this Thesis

CHAPTER 1: THE CONCEPTS AND LEGAL FRAMEWORK GOVERNING THE THREAT OR USE OF FORCE IN BIEN DONG

1.1 The concept of the threat or use of force at sea

1.1.1 The threat or use of force in international relations

a The term “use of force”

Use of force is considered as a traditional but controversial aspect in publicinternational law However, the term “use of force” has not been officially defined yetbut comprehended flexibly in each practical situation The word “force” is properlythe central question of this term

The noun “force” appears in many dictionaries with definitions as follow:The Oxford Dictionary [48, p 337-338] indicates that “force” embodies (1) aperson or thing that has a lot of power or influence; (2) power or influence thatsomebody/ something has; (3) an effect that causes things to move, change direction

or change shape; (4) violent physical action used to obtain or achieve something; (5)soldiers or others whose job is to fight or to protect people; (6) a group of people whohave been organized for a particular purpose; (7) the physical strength of something as

it hits something else; (8) a unit for measuring the strength of wind

The website Dictionary.com [24] shows that “force” means (1) physical power

or strength possessed by a living being; (2) strength or power exerted upon an object,physical coercion, violence; (3) strength, energy, power, intensity

The website Dictionary.cambridge.org [25] provides a vast array of meanings

of the word “force” The definitions that are most relevant to this matter include (1)action of making something happen or making someone do something difficult,unpleasant, or unusual, especially by threatening or not offering the possibility ofchoice; (2) action to make certain that an urgent problem or matter is dealt with now;(3) strong influence and energy, or a person with strong influence and energy; (4)

power to make someone do something, or to make something happen, especiallywithout offering the possibility of choice; (5) an organized and trained military group;(6) force is also military strength.

In the most general understanding perspective, in the relationship among states,the term “use of force” is determined as to use the armed forces aiming against

economic or politic means is considered as the use of force only when the implication

Constantinos Yiallourides states that Art 2(4) UN Charter makes it clear thatthe use of force by States is prohibited only in their international relations Therefore,

to come under the prohibition, the use of armed force by a State must be directedagainst the territory of another State The prohibition, hence, does not cover the use offorce purely internal to one State, such as clashes between government armed forcesand rebel groups within the same State or forcible law enforcement actions againstprivate individuals [20, p.34]

It is noted that Art 2(4) UN Charter seeks to prohibit the use of force by oneState against another as opposed to forcible measures which hold some foreignelements Not every forcible act within a State that has a foreign element will affectthe international relations of the two States The arrest of a foreign national by thepolice within a given State, for example, will typically constitute a law enforcementexercise, not engaging Art 2(4) UN Charter Nevertheless, where force is used in aninter-state relationship between the agents of two States, whether military or policeunits, will affect the States’ international relations and trigger the application of Art.2(4) UN Charter [20, p.34]

Additionally, the concept of force also includes armed powers and other armed powers, even economic and political powers [6, p.358]; coercive intent reflects

non-the objectively discernible aim or effect of “forcing non-the will of anonon-ther state” to accept

a new status quo, according to Olivier Corten [19]

b The term “threat of force”

Regarding the term “threat of force”, Ngo Huu Phuoc argued that the concept

of the threat of force “are the actions which are used by the subject of international

received much less attention than other elements of Art 2(4) UN Charter It is noteasy to answer what the term “threatening” covers Threats are usually followed byactual military operations, and therefore, the situations are discussed as violations ofthe prohibition of using armed force The threat and use of armed force are in fact twodistinct violations, but states pay more attention to uses, and judicial organs seem tohave a practical approach that “more serious” conduct (use of armed force) covers

“less serious” conduct (threat of armed force)

The action of arming, forming alliances, and building self-defence capability isnot a violation of Article 2(4) It is undoubtedly difficult, if not impossible, to

distinguish between the arming for defensive or offensive purposes In the Legality of

the Threat and Use of Nuclear Weapons case, the ICJ found that the possession of

nuclear weapons in itself does not amount to the violation of Article 2(4), unless theparticular state intends to direct them directly against the territorial integrity orpolitical independence of a state, or against the purposes of the United Nations orwhether it would necessarily violate the principles of necessity and proportionality.[52]

The ICJ indicated that there is a close connection between a “threat” and a

“use”; in other words, the legality of the threat depends directly on the legality of theintended use If a state or an alliance sends the potential aggressor a message thatarmed force will be used repel its armed attack, this is legal because the state or the

alliance is “threatening” with legitimate self-defence However, if a state demandsthat another state handed over a part of its territory and adds that it is prepared to usearmed force if the other state is not willing to comply, the state is threatening with anillegal form of armed force and is violating Article 2(4) [52]

Thus, the threat to use force is conceptually similar to the actual use of force

In the viewpoint of Brownlie, a threat of force consists of “an express or impliedpromise by a government of a resort to force conditional on non-acceptance of certaindemands of that government If the promise is to resort to force in conditions in which

no justification for the use of force exists, the threat itself is illegal”.[20, p.46]

It is, therefore, illegal for a State to threaten to resort to force to secureterritory from or settle a territorial dispute with, another State Nevertheless, thedeclared readiness of a State to use armed force to defend its territory against thebelligerent occupation, in principle, does not constitute a prohibited threat of force It

is, moreover, generally agreed that the type of threat of force prohibited by Article2(4) UN Charter should necessarily have a coercive intent directed towards specificbehaviour on the part of another State The piling-up of military arms or the conduct

of military exercises, though implying a potential threat of force against a given State,would not in itself constitute a prohibited threat of force”.[20, p.46]

According to the ICJ, in order to be lawful, the declared readiness of a State touse force ‘must be a use of force that is in conformity with the Charter’ As a result,the signalled readiness of a forcible defensive reaction by the victim of an armedattack would not violate Article 2(4) of the UN Charter ”.[20, p.46] In reality, it is

complicated to draw a line between threats and uses In the Military and Paramilitary

Activities in and against Nicaragua case, the ICJ was not convinced that the military

manoeuvres held by the United States near the Nicaraguan borders were threats ofarmed force [52]

In fact, it is not entirely necessary for differentiating the concept of the use offorce and threat of force First and foremost, the two norms share the same legal

framework Moreover, in the vast majority of cases, the two forms of actitivitiescombine with each other to constitute the international resposibiltity of one state.

c Direct and indirect use of force

Constantinos Yiallourides argued that direct forms of the use of force include

an open invasion or attack by regular military forces directed at the territory ofanother State It also applies to the given territory is subject to a dispute but remainsunder the administration of the other party Direct use of force also includes cross-border shooting, outside or within the disputed area, as well as the laying of mines inthe disputed area.[20, p.32]

Regarding indirect forms of the use of force, this forms encompass theparticipation of a State in the use of force, either through another State, or by armingand training private individuals (for example, unofficial bands of irregulars,mercenaries, or rebels organised in military fashion), who then carry out armedoperations and other acts of violence against another State Nevertheless, the meresupply of funds to such groups does not in itself constitute a violation of theprohibition on the threat or use of force A violation of the prohibition on the threat oruse of force could be established in the context of a territorial dispute where, forinstance, first, one of the parties has supported private violence through militarytraining and/ or provision of arms and, second, the units receiving the support thenengaged in the threat or use of force against the claimant party to gain control over adisputed territory [20, p.32]

1.1.2 The threat or use of force at sea

a The notion of the threat or use of force at sea

It can be learned from the norm “threat or use of force” in internationalrelations, the threat or use of force at sea could be understood as the use of maritimeforces to conduct operations on maritime spaces against an independent sovereignState or to pressure, threaten another country to achieve certain goals Accordingly,

the threat or use of force at sea at present is not only manifested as aggressive acts inreality but also an imposition of unreasonable will preventing other countries fromexercising their legitimate rights and interests in their jurisdiction maritime zones.

There remain some differences the threat or use of force at sea and that on theland domain as what differentiates the sea and the land The sea is a uniqueenvironment formed by liquid water which is always moving People cannot operatedirectly on the maritime spaces like on the land domain but depend on technicalmeans Therefore, the maritime armed forces have the following basic characteristics:

being equipped with specific weapons on the maritime spaces; (iii) being very highlysynergistic with other forces on land and in the air,

Besides, under the law of the sea, all ships of every state enjoy the freedom ofnavigation and other legitimate rights Additionally, the coastal States also enjoysovereignty and sovereign rights and jurisdiction in the sea areas in the vicinity oftheir coasts, which causes law enforcement against foreign vessels Furthermore, incontested waters, the claimants are prepared to assert their claims by the use of theirnavies, coast guards or other State-owned vessels As a result of this, such assertionsmay include aggressive actions sometimes akin to a use of force against the flag State

of the vessels affected, which increases the potential for tension and conflict andviolates the principle of prohibiting the use of force in international relations.[69,p.450]

b The characteristics of the threat or use of force at sea

From theoretical approach in section 1.1.1, the threat or use of force at seamust include all characteristics of the threat or use of force in general meaning andsome special aspects as happened in the maritime zone

First, in any circumstances, the threat or use of force must contain the fact that

one state puts pressure to another state by forcible measures This coercion is

embodied in a variety of forms of operations in reality, for instance, using armedforces to occupy maritime insulars or to control maritime zones beyond itsentitlement, forcing another state not to exercise its legitimate rights in its waters, etc.This criterion plays a paramount importance in the identification of the threat or use

of force in such sophisticated international relation Therefore, the commondenominator of the forcible actions is the use of power, which force the others doadhere to one’s will

Second, the threat or use of force intentionally goes against an independent and

sovereign state or others’ interests or in some specific situations it goes withoutconsent of one involved party Back to the history of the law of nations, threat or use

of force was classically used to settle disputes In other words, the force was aprimary mean of solving the conflicts between states It is the interests that are indemand for numerous countries, which causes the threat or use of force Accordingly,whenever there exist such interests, the aggressive state stands in front of an option tothreaten or use force to achieve those interests In some particular disputes that aremanaged by consensus provisions in advance, the unilateral activities lacking theconsent of remain parties are likely considered as one characteristic of the threat oruse of force

Third, the actions of threatening or using force possibly violate the status quo

or have the intention of altering the status quo Status quo is a Latin phrase meaning

the existing state of affairs, particularly with regard to social or political issues Thiscriterion stems from the previous in the aspect that the aggressive state would resort toforce to gain the interests

Fourth, the actors of the threat or use of force at sea must be the maritime

armed forces or official maritime forces This criterion distinguishes the threat or use

of force at sea in international law with piracy or other acts of violence at sea.However, China has been sufficiently taken advantages of paramilitary forces The

legal status of official maritime forces is the key point to analyse the “grey zone”conflicts in Bien Dong.

On the contrary to the assertation above, Jinxing Ma and Shiyan Sun arguedthat the nature of the use of force at sea – armed conflict or law enforcement – isdetermined by the background, basis and forms of the use of force, rather than by theidentity of the actors and their competence under domestic law The users of force atsea consist of States, organised armed groups and private entities, mainly privatemilitary and security companies, pirates, smugglers and other criminals Naval battlesbetween States and organised armed groups are quite rare; for example, the LiberationTigers of Tamil Eelam is probably the only non-State armed group ever to have itsown navy during a non-international armed conflict The targets of the private militaryand security companies’ use of force are mainly pirates and/ or armed robbers at sea

In terms of the scale of force used and the types of arms used, and in view of maritimesecurity practice, the use of force by private military and security companies andcriminal gangs can hardly affect the maritime environment In conclusion, however,Jinxing Ma and Shiyan Sun stated that it is the use of force by States that has the mostsignificant impact and therefore merits the most attention [34, p.520]

Fifth, since the use of "state-of-the-art" technical means on operating at sea,

the lethality could accordingly be more serious As a matter of fact, the navy and airforce that are main forces participating wars at sea are among the most modern armedforces of coastal states This raises grave concerns for coastal parties in disputes

Sixth, the legal status of each maritime zone is distinctly classified as provided

in UNCLOS whereas the land is entirely within the separate, absolute right of a state.The legal status of individual maritime zones also is the base of examining whetherthe threat or use of force at sea is legal or illegal in each specific case

It is the prerequisite prohibition in international relation, though, in themaritime domain the threat or use of force could be operated under the cover of lawenforcement One of the core contents of jurisdiction over the sea is the right to apply

and enforce the law of coastal state within the given maritime zones Therefore, indisputed waters, the law enforcement activities of the armed forces at sea are prone toacts of threatening and using force at sea, because these actions carry the will of acountries want to assert its maritime claims.

c The distinction between maritime law enforcement and the use of force at sea

David H Anderson stated that the rules of international law governing the use

of force at sea as a measure of law enforcement by coastal States were primarilydeveloped by the rulings of international courts and tribunals and secondarily bytreaties Different rules apply to the threat or use of force in inter-State relations.[22,pp.233-243]

With the same assertation, Jinxing Ma and Shiyan Sun supposed that thecontexts of State use of force at sea include armed conflict at sea and maritime lawenforcement Each has different legal bases.[34]

Besides, Patricia Jimenez Kwast explained that the distinction betweenmaritime law enforcement and the use of force at sea was as intricate in law as it isfundamental in practice Many international legal aspects regarding the determination

of the nature of forcible measures against foreign ships at sea have remained largelyunexplored It is clear that the use of police force in maritime law enforcement, asconsidered above, is to be distinguished from the use of force in internationalrelations However, the difficulty is that the latter category, when applied at sea, mayinvolve similar measures as those that occur in case of the former And distinguishingbetween the two, to say the least, “is not always easy”.[49]

Moreover, Patricia Jimenez Kwast also confirmed that in determining thecharacter of an action under review it will in this sense make little legal differencewhether the ‘force’ to be distinguished from law enforcement action will concern the

actual use of force, or the threat of use of force Accordingly, the considerations as tothe functional objective involved will be essentially the same [49]

As a matter of fact, the distinction between a resort to armed force, which maylead to international armed conflict, and other measures below the threshold is morecomplicated to draw in reality than in theory It is the situation that states resort toconduct that does not involve the use of traditional methods and means of warfare butthat notwithstanding may be regarded as aggression, coercion or violence.[69]

1.2 The set of rules governing the threat or use of force at sea

All states have the responsibility to protect and maintain the peace and security

at sea, which has been recognised by both treaty law and customary international law

1.2.1 General principles and provision of public international law

a The prohibition on the threat or use of force in international relations

As it is named after, the first and foremost fundamental principle ofinternational law governing the use or threat of force at sea must be the principle ofthe prohibition on the threat or use of force in international relations

Christine Gray stated that the starting point for any examination of the law isthe prohibition of the use of force in Art 2(4) of the UN Charter [16, p.6] Theprohibition on the inter-state use of armed force is a central feature of the Charter and

is found in Art 2(4) UN Charter which proclaims that: [52]

All Members shall refrain in their international relations from the threat oruse of force against the territorial integrity or political independence of anystate, or in any other manner inconsistent with the Purposes of the UnitedNations

This provision has been rightfully described as a “cornerstone of the peace” inthe UN Charter or “the heart of the UN Charter” and “the basic rule of contemporarypublic international law” Because never before had nations agreed upon so

comprehensive and far-reaching prohibition to use armed force Accordingly, RenéVärk argued that Art 2(4) UN Charter was one of the most fundamental progress inthe system of international relations, which throughout history has valued the freedom

of states to wage war This fundamental principle of contemporary international lawwas established to raise the hopes expressed in the Charter, namely internationalpeace and security [52]

Relating the role of the non-use of force principle, there is a debate in ILC

about whether it is jus cogens On the one hand, some argue that threat or use of force

is considered to be jus cogens or “peremptory norm” of international law in which no

state has the right to depart from the rule prohibiting the use of force Therefore, any

attempt to modify this norm must satisfy the elements of state practise and opinio

juris.[36]

Conversely, other refuse because the use of force is legal in two situations: (1)under a UN Security Council resolution under Art 42 UN Charter 1945; or (2) in self-defence under Art 51 UN Charter 1945 Hence, only prohibition of aggression is anorm of jus cogens To be more precise, document A/CN.4/L.936 of ILC dated on 29May 2019 “Peremptory norms of general international law (jus cogens)” indicates theprohibition of aggression is a peremptory norms of general international law.[29]

In addition, Statement of the Chair of the Drafting Committee on document A/CN.4/L.936 shows that the prohibition of aggression proposed adding the phrase “oraggressive force” The revised proposal contained only the “prohibition ofaggression” Some members noted that the prohibition of aggression could bereformulated more broadly as “the law of the Charter concerning the law of the use offorce” The Drafting Committee kept the formulation “prohibition of aggression”based on its most recent relevant reference in the 2001 articles on State responsibility.[17]

It is clear from document A/CN.4/L.936, Draft conclusion 2, that jus cogens

norm has been defined as:

A peremptory norm of general international law (jus cogens) is a normaccepted and recognized by the international community of States as awhole as a norm from which no derogation is permitted and which can bemodified only by a subsequent norm of general international law havingthe same character [29]

In other words, jus cogens norms represent the overriding norms of

international law that must be respected at any time with no excuse (there are no

circumstances precluding wrongfulness) As jus cogens norms are essentially similar

to customary international law they are legally binding on all members of theinternational community regardless of whether or not they have expressed theirapproval or disapproval of a particular norm While a treaty obligation is owed to

other parties of the particular treaty, the obligation under jus cogens norm is owed, as

a legal fiction, to the international community as a whole, every state may feel that itsessential interests have been breached and consequently not only the state that isdirectly injured, but also any other state, is entitled to invoke the responsibility of theviolating state.[52]

Futhermore, the application of non-use of force principle is also one of themost controversial areas of international law; even from the early days of the UNnumerous disagreements among states to such provision were apparent.[6, p.7]

Moreover, the ICJ in the case Military and Paramilitary Activities in and against

Nicaragua (Nicaragua v United States of America) in 1986 apparently regarded this

UN Charter provisions as dynamic rather than fixed, and thus as capable of changeover time through state practice To be more precise, Art 2(4) UN Charter is certainly

progressive because it stipulates on the use of force and not war [52]

The vivid example of this is when Japan invaded Manchuria (China) in 1931.Japan did not declare war against China but claimed that its military operations didnot amount to war and were not in violation of international law In fact, Japan’sactions were war in reality, but not war in legal terms and, consequently, beyond the

scope of the intertemporal international law, such as Kellogg-Briand Pact Due tosuch 1930s practice, the drafters of the UN Charter decided to replace the term “war”with the term “force” [52], which takes into account the factual reality and covers allrisks for peace and security.

As a consequence of that, when the UN Charter was adopted, the focus shiftedaway from whether a State declares war or commits an “act of war,” and instead nowfocuses more on whether a nation has engaged in a “use of force” [35] On the groundthat serveral long-lasting conflicts remain, the role of the principle prohibiting thethreat or use of force seems to be indispensable

Unlike many treaties, the UN Charter does not contain a dedicated section thatdefines terms used within the treaty, so there is no exact definition of what wasintended by the phrase “use of force” Therefore, one must first consider the “ordinarymeaning” of the treaty terms in their specific context Applying this standard forinterpretation, one leading commentary on the UN Charter has assessed: Already thescope of the fundamental notion of ‘force’ is not undisputed The term does not coverany possible kind of force, but is, according to the correct and prevailing view, limited

to armed force.[35]

Evidence for this conclusion is embodied in the object, context, and purpose ofthe Charter Therefore, the text and context of the Charter strongly suggest that theprohibition of Art 2(4) is centred on the use of armed force This original meaning ofArt 2(4) is also confirmed by the drafting and negotiating process of the Charter.Assuredly, the drafters and negotiators of the UN Charter intended for the paragraphthat would eventually become Art 2(4) to cover the threat or use of armed force.[35]

Another important element of the prohibition on the threat or use of forcerelates to the notion of territorial integrity Art 2(4) of the UN Charter 1945 provides

that members shall refrain from the threat or use of force “against the territorial

integrity… of any State” [20, p.47] However, territorial status is applied to internal

waters and territorial sea only Therefore, it is also the most controversial issue that

whether the matter of threat or use of force at other maritime domains has the samenature with the prohibition on the threat or use of force provided in Art 2(4) UNCharter 1945 Arguably, the threat or use of force at sea is examined to be within thescope of the prohibition of the threat or use of force as provided in Art 2(4) UNCharter 1945 only when such operations comprise of the characteristics as mentioned

in the previous section

b Armed attack and self-defense

Another concept in the UN Charter that is related to “use of force” is whatconstitutes an “armed attack” Art 51 UN Charter recognizes that the Member States

of the UN have an “inherent right” of self-defense if “an armed attack occurs” againstthat State:

Nothing in the present Charter shall impair the inherent right of individual

or collective self-defense if an armed attack occurs against a Member ofthe United Nations, until the Security Council has taken the measuresnecessary to maintain international peace and security Measures taken byMembers in the exercise of this right of self-defense shall be immediatelyreported to the Security Council and shall not in any way affect theauthority and responsibility of the Security Council under the presentCharter to take at any time such action as it deems necessary in order tomaintain or restore international peace and security

Whereas Art 2(4) of the Charter prohibits a State from using force, Art 51 isnot similarly phrased as a prohibition on a State committing an armed attack Instead,

it is indirectly framed as an action by one State that can trigger proportionateconsequences for another State or States Specifically, if a State (or non-State actor)commits an armed attack, then the attacked State may legally use force in self-defense.[35]

Accordingly, what exactly constitutes an “armed attack”? As it is said above, a

“use of force” in the sense of Art 2(4) UN Charter was intended to mean the use ofarmed force Although the textual and contextual evidence of the Charter suggeststhat the phrases “use of force” and “armed attack” have different meanings, thedrafters of the Charter would presumably have used the same phrase in both

circumstances In discussing the relationship between Art 51 and Art 2(4), The

Charter of the United Nations: A Commentary as cited by Jonathan G Odom noted

that “Arts 51 and 2(4) do not exactly correspond to one another in scope, i.e., notevery use of force contrary to Art 2(4) may be responded to with armed self-defence” That commentary concludes that an armed attack is “a narrower notion”rather than a threat or use of force It is significant to clarify this difference because itmeans a State is restricted in its response options (i.e., to actions other than usingforce in self-defense) if it has been the recipient of another State’s illegal use of forcethat does not rise to the level of an “armed attack” The possible legal impact of thisdifference has sometimes been referred to as a “gap” [35]

* Criteria for Exercising Self-defence [52]

An act of self-defence is lawful only when it is immediate, necessary andproportional These well-known criteria are not entirely fixed but flexible in order not

to render self-defence a mere theoretical option

When states respond in self-defence, their action must follow immediately andwithout any delay right after the armed attack has occurred, otherwise, the militaryoperation is simply an armed reprisal In reality, depending on each specificcircumstance, it may take hours or even days before a state is ready to exercise self-defence

This criterion demands that there be no possible alternative instead of usingarmed force It is plausible to require the state to consider other peaceful means ofsettling disputes if the armed attack was an isolated or insignificant incident

However, in the case of an extensive attack, the state may use armed force more freely

as a first resort

A determination on necessity is assuredly subjective; estimatingproportionality is not an accurate task also The most appropriate outcomes areachieved after conflicts have ceased when it is probable to calmly andcomprehensively assess the circumstances The purpose of self-defence is to resist anddesist the attack, but this does not mean that the military operation must stop.Regrettably, proportionality is not the decisive criterion for assessing the legality ofthe use of armed force in self-defence The armed conflict may escalate when theaggressor resumes its offensive actions and when the use of armed force reaches thelevel which is disproportional to the initial attack Once the war is exploding theexercise of self-defence may bring about the loss of the aggressor’s armed forces

c State resposibility

State responsibility, as an opinion of Malcolm Shaw [42, p.778], is afundamental principle of international law, arising out of the nature of theinternational legal system and the doctrines of state sovereignty and equality of states

It provides that whenever one state commits an internationally wrongful act againstanother state, international responsibility is established between the two A breach of

an international obligation gives rise to a requirement for reparation

The underlying concepts of State responsibility, including attribution, breach,excuses, and consequences, are general in character Specific treaties or rules mayalter these underlying concepts in some aspect; otherwise, they are considered andapply unless excluded These standard assumptions of responsibility, on the basis ofwhich specific obligations of States exist and are applied, were reviewed by the ILCover more than 40 years On 10 August 2001, the Draft Articles on Responsibility ofStates for Internationally Wrongful Acts was adopted [33]

The ILC’s commentary on the Draft Articles on Responsibility of States forInternationally Wrongful Acts indicates that the peremptory norms that are clearlyaccepted and recognized include the prohibitions of aggression, genocide, slavery,racial discrimination, crimes against humanity and torture, and the right to self-determination [28]

Art.1 of the Draft Articles on Responsibility of States for Internationally

Wrongful Acts stipulates that: “Every internationally wrongful act of a State entails

the international responsibility of that State” The elements of an internationally

wrongful act of a State are firgured out in Art 2 of the Draft Articles: There is aninternationally wrongful act of a State when conduct consisting of an action oromission: (1) is attributable to the State under international law; and (2) constitutes abreach of an international obligation of the State

In terms of legal consequences of an internationally wrongful act, the ILC’scommentary on the Draft Articles points out that the core legal consequences of aninternationally wrongful act are the obligations of the responsible State to cease thewrongful conduct (Art 30) and to make full reparation for the injury caused by theinternationally wrongful act (Art 31) Where the internationally wrongful actconstitutes a serious breach by the State of an obligation arising under a peremptorynorm of general international law, the breach may entail further consequences both forthe responsible State and for other States Particularly, all States in such cases haveobligations to cooperate to bring the breach to an end, not to recognize as lawful thesituation created by the breach and not to render aid or assistance to the responsibleState in maintaining the situation so created (Arts 40–41).[28]

1.2.2 Law of the sea

a Peaceful use of the seas

There is no doubt that UNCLOS is the most comprehensive and universaltreaty governing legal matters relating to the sea With respect to the use of force at

sea, Art.s 19(2)(a), 39(1)(b), 88, 141 and 301 UNCLOS 1982 are the main

contribution to the principle “peaceful use of the seas”, definitely, Art 301 UNCLOS

1982 stipulates that:

In exercising their rights and performing their duties under this

Convention, States Parties shall refrain from any threat or use of force

against the territorial integrity or political independence of any State, or inany other manner inconsistent with the principles of international lawembodied in the Charter of the United Nations (emphasis added)

Sarah Goyette argued that in the phrase ‘threat or use of force’, the term ‘force’can be understood as generally mean coercion and aggressiveness or even violence.The term ‘threat’ may be regarded as generally meaning a menace or imminentdanger Consequently, the expression ‘threat or use of force’ may be assumed torepresent the possibility or actual use of aggressive or violent actions Hence, themajor meaning of the clause “States Parties shall refrain from any threat or use offorce” can consequently be regarded as meaning that countries which ratified theUNCLOS should abstain to engage in possible or actual aggressive or violent actions.[54]

With the position of a general provision, Art 301 applies to all the regimesprovided in the UNCLOS Theoretically saying, it can be observed that the maritimezones, which States exercise or may exercise sovereignty, are within the scope of theprohibition of the threat or use of force To be more precise, those are the internalwaters, territorial seas, archipelagic waters, and straits used for internationalnavigation As a consequence of this, the UNCLOS recognises this idea in Art 19(2)(a), 39(1)(b)

Sarah Goyette interpreted that Art 301 would thus even apply to the othermaritime zones where the jurisdiction of the State is limited, but the freedom of theseas applies In particular, Art 301, as the two others, contains a third element againstwhich the threat or use of force may be indirect occurred: “in any other manner

inconsistent with the principles of international law” This expression would thus

replace the term sovereignty.[54]

This Thesis, to some extent, agrees with the above interpretation, moreover,adds the perspective of “unsettled sovereignty” or “mobilities” and “more-than-territorial configurations” of state Art 236 UNCLOS 1982 recognises the sovereign

immunity of “any warship, naval auxiliary, other vessels or aircraft owned or

operated by a State and used, for the time being, only on government non-commercial service” In practice, the collision between the two state-owned vessels could lead to

the conflict between the two State-flagged

Furthermore, in this modern era, due to high-tech military innovation,aggressive actions could happen in any maritime areas including high seas or zones.Therefore, Art 301 should better be understood as a principle that prevents all kind ofhostile state-to-state activities from the sea Art 301 of the UNCLOS 1982 actuallyreaffirms Art 2(4) UN Charter for the sea Consequently, it could be assumed thatArt 301 of the UNCLOS 1982 also codifies that prohibition more explicitly applied

is continental or island The notion of territory is connected to a state’s sovereignty,namely, those geographical areas over which sovereign jurisdiction may be exercised

to the exclusion of all other states The central norms of sovereignty and territorialintegrity allow a state with sovereignty over a defined territory to behave freely upon

that territory and to bar other states from acting upon it These norms protect thesovereign state from unilateral territorial aggression or violation from other states.[19]

In international law of the sea, it is most obvious that in the maritime areasunder sovereignty and jurisdiction of one state, the coastal state has the right toimpose its laws on maritime activities of other states in its maritime zones, which isthe foundation of the use of force in law enforcement at sea The two forms of “force”could hardly be distinguished well in the maritime domains, especially in theoverlapping areas

No matter how vitally the issues of use of force contributes to the internationallaw on the sea, the provisions relating to this aspect are few and blur In other words,

it is in the law of the sea where the ambiguousness between threat or use of force atsea and the maritime law enforcement exist

When implementing Art.s 19 and 38 of UNCLOS, an international armedconflict may come into existence if the coastal State uses its armed forces to compelthe warship to leave the territorial sea or strait Notably, the ICRC Commentary at

paragraph 227 indicates that “use of force at sea… motivated by something other than

a State’s authority to enforce a regulatory regime applicable at sea” Unfortunately,

this paragraph provides neither clarification nor a reference to a situation that could beconsidered as triggering an international armed conflict by the use of force againstforeign merchant vessels Hence, the absence of a legal basis or the disproportionatenature of the force used will scarcely suffice to qualify as a resort to a use of forceagainst the flag State.[69, p.459]

Besides, the Art 224 UNCLOS 1982, with the name exercise of powers ofenforcement, stipulates that:

The powers of enforcement against foreign vessels under this Part may

only be exercised by officials or by warships, military aircraft, or other

ships or aircraft clearly marked and identifiable as being on government service and authorized to that effect (emphasis added)

It can be learned from Art 224 UNCLOS 1982 that armed forces canparticipate in law enforcement activities in some instances as provided Accordingly,the vague line between the use of force at sea in inter-state relations and the use offorce in maritime law enforcement appears in two directions: (1) using military armedforces in law enforcement activities and (2) threatening or using force under the cover

of law enforcement Empirically saying, the latter is more wide-spread and becomesthe great challenge to the peace and security of the sea, especially to contested waters

1.2.3 International maritime law

If the law of the sea expressed the idea of assessing an act via the purpose ofactor whether or not it is peaceful use of the seas, then international maritime lawwould present the manner how the threat or use of force occurs actually at sea.Accordingly, the threat or use of force can be manifested by the act of non-respect ofthe rules governing the safety of navigation at sea There exist two codes that need to

be considered

(1) Convention on the International Regulations for Preventing Collisions at Sea 1972 – COLREGs 72

Convention on the International Regulations for Preventing Collisions at Sea,

1972 (COLREGs) was adopted on 20 October 1972 and came into force on 15 July

1977 In this Convention, it is obvious to figure out four among the rest are mostinvolved They are rules 5, 7, 8, 10 of COLREGs

According to the current status of Conventions provided by IMO [63], allcoastal states of Bien Dong are contracted parties of this Convention Hence, theserules would be more straightforward to be applied in this area

(2) Code for Unplanned Encounters at Sea – (CUES) 2014

Code for Unplanned Encounters at Sea (CUES) was established in Qingdao,

countries, including: Australia, Brunei, Cambodia, Canada, Chile, China, France,Indonesia, Japan, Malaysia, New Zealand, Papua New Guinea, Peru, Philippines,Russia, Singapore, South Korea, Thailand, Tonga, US and Vietnam This Code is notlegally binding; instead, it is a coordinated means of communication to maximisesecurity at sea.[18]

Moreover, the CUES proposes safety measures and a means to narrow mutualinterference, to restrict risk, and to promote communication when naval vessels ornaval aircraft encounter each other in an unplanned manner.[18]

In addition, the CUES applies in Bien Dong through the Joint Declaration onthe application of the Code of Conduct for Unintended Encounters on the Sea in the

2.8.1 CUES, which claims commanding officers should avoid:

tube launchers or other weapons towards the encountered ship or aircraft

objects towards the ship or aircraft encountered

encountering ships or aircraft

encountered

1.2.4 International law on armed conflicts at sea

During armed conflicts, the use of force at sea is lawful provided that the force

is exercised distinctively, precautionarily, proportionally and necessarily