GLOSSARY
1. Definitions of Key Concepts
Self-defence: A fundamental principle of international law, formalized in customary law and codified under Article 51 of the UN Charter. It permits a state to use force in response to an "armed attack," though the scope remains contested regarding "anticipatory" self-defence. The legality of such actions is governed by the Caroline criteria: the necessity of self-defence must be "instant, overwhelming, leaving no choice of means, and no moment for deliberation," and the response must be proportionate.
Shared expectations: A concept closely aligned with opinio juris sive necessitatis, representing a collective psychological belief among states that a particular practice is not merely a habit but a legal obligation. This differentiates legal custom from mere international comity or courtesy.
Sovereignty: Historically defined by Jean Bodin in Six Books of the Commonwealth (1576) and later Thomas Hobbes in Leviathan (1651). It refers to the supreme authority within a territory. In the modern post-Westphalian sense, it implies "sovereign equality" (Art. 2(1) UN Charter), where states are independent from external authority unless they explicitly consent to be bound.
State immunity: Derived from par in parem non habet imperium (equals have no authority over each other). It protects states from the jurisdiction of foreign courts.
Immunity ratione personae: Absolute immunity granted to high-ranking officials (Heads of State, Ministers for Foreign Affairs) while in office for all acts.
Immunity ratione materiae: Functional immunity granted for acts performed in an official capacity, which may persist after leaving office.
Structural realism: A school of IR theory (Neorealism), pioneered by Kenneth Waltz in Theory of International Politics (1979). It posits that the anarchic nature of the international system creates a "security dilemma" where states must maximize power to ensure survival, rendering international law a reflection of power dynamics rather than a constraint on them.
Transnational law: Conceptualized by Philip Jessup in 1956, it describes the legal framework governing actions that cross national borders—breaking the traditional binary between public international law (state-to-state) and private international law (conflict of laws between individuals).
Treaty: Defined by the Vienna Convention on the Law of Treaties (1969) under Article 2(1)(a). It is an international agreement concluded between States in written form and governed by international law, regardless of its nomenclature (Covenant, Charter, Protocol, or Statute).
Universality and Erga Omnes: The principle that certain norms (like the prohibition of slavery or genocide) are so fundamental that duties are owed to the international community as a whole. Any state has a legal interest in their protection, regardless of whether it was directly affected.
Universal jurisdiction: The doctrine that any state may prosecute individuals for crimes deemed so heinous they are "enemies of all mankind" (hostis humani generis). Examples include piracy, war crimes, and crimes against humanity, allowing prosecution irrespective of where the crime occurred or the nationality of the parties.
Veto: Established under Article 27(3) of the UN Charter, identifying that substantive decisions of the Security Council require the concurring votes of the Permanent Five (P5). A single negative vote from a P5 member prevents the adoption of a resolution, effectively centering global security enforcement on the consensus of the most powerful states.
CHAPTER 1: THE DEVELOPMENT AND NATURE OF INTERNATIONAL LAW
1. Introduction
International law is the normative framework coordinating the conduct of global actors. Historically described as jus gentium (Law of Nations), it has transitioned from a Eurocentric system used to validate colonial land-grabs into a universal legal order. It addresses "hard" issues like the use of force and "soft" issues like international postal services or satellite orbits.
2. Development and Historical Context
2.1 Prehistoric Beginnings
Early nomadic groups and tribes utilized rudimentary forms of international norms to manage resource scarcity and conflict.
The Sanctity of Diplomats: Messengers were often granted safe passage even between warring tribes, a precursor to the 1961 Vienna Convention on Diplomatic Relations.
Neutral Zones: Designated areas for trade (silent trade) allowed for economic exchange without the risk of immediate violence.
2.2 Ancient Civilizations
The Mesopotamia Precedent: Around 3100 BC, the Lagash-Umma treaty settled a dispute over the "Gu-Edin" territory. It is significant for being the first recorded use of arbitration and the invocation of divine witnesses to guarantee compliance.
The Treaty of Kadesh (1259 BC): Concluded between Pharaoh Ramses II and King Hattusili III. It is the oldest surviving complete treaty text, featuring clauses on:
Non-Aggression: A perpetual peace between the two empires.
Mutual Defence: An early form of collective security against internal or external threats.
Extradition: Returning political dissidents or skilled laborers to their original sovereign.
The Greco-Roman Contribution: Ancient Greece developed isopoliteia (equal citizenship rights between cities). Rome contributed jus fetiale, a religious-legal code for declaring war (bellum iustum) and concluding peace, ensuring that Roman expansion was legally justified.
2.3 The Medieval Interregnum and Lex Mercatoria
While the collapse of Rome led to legal fragmentation, the Catholic Church maintained continuity through Canon Law, which influenced doctrines of "Just War." Concurrently, the Lex Mercatoria emerged as a customized body of law created by merchants for merchants to handle maritime trade, debt, and contracts, operating independently of the feudal land-based legal systems.
2.4 The Transition to Modernity: Naturalism vs. Positivism
The School of Salamanca: Francisco de Vitoria challenged the "Right of Discovery," arguing that indigenous peoples in the Americas possessed natural rights and that war against them was only justified in very limited circumstances.
The Grotian Tradition: Hugo Grotius (1583-1645) synthesized natural law (reason) with voluntarism (the will of states). He famously argued that international law would remain valid etiamsi daremus (even if we were to concede that God does not exist).
The Positivist Turn: By the 19th century, thinkers like John Westlake argued that law is not found in nature but is created by the express consent of states through treaties and customs. This led to the "lotus principle": states are free to do anything not explicitly prohibited by international law.
3. Contemporary Understandings and Challenges
3.1 The Debate on Enforcement
The Command Theory: John Austin argued that without a "sovereign commander," international law is merely "positive morality."
Modern Counter-arguments: H.L.A. Hart argued that international law is a system of "primary rules" of conduct, even if it lacks "secondary rules" of change and adjudication as sophisticated as domestic systems. Participation in the WTO or UN is seen as a voluntary exercise of sovereignty rather than a loss of it.
3.2 The Post-WWII "Constitutionalization"
The 1945 UN Charter shifted the focus from the "Right to War" to the "Prohibition of Force." This era introduced:
Individual Responsibility: The Nuremberg Trials established that individuals, not just states, can be held liable for international crimes.
Human Rights: The UDHR (1948) began the process of making the individual a subject, rather than just an object, of international law.
CHAPTER 2: THE GENERAL PRINCIPLES OF INTERNATIONAL LAW
1. The Criteria for Statehood
Under the Montevideo Convention (1933), an entity is a state if it meets four objective criteria. These are often debated through two competing theories:
Declaratory Theory: Recognition by other states is merely an acknowledgment of existing facts. If the four criteria are met, the state exists.
Constitutive Theory: An entity only becomes a state through the act of recognition by other existing states.
The 4 criteria are:
Permanent Population: No minimum size is required (e.g., Nauru or Vatican City), but the population must be stable.
Defined Territory: Borders do not need to be perfectly settled (e.g., Israel), but there must be a consistent core territory.
Government: Effective central control is traditionally required, though this is relaxed for "failed states" to maintain their legal existence.
Capacity to enter into relations: This distinguishes a state from a colony or a sub-unit of a federation (like California or Quebec), which may have people and territory but lacks independent diplomatic standing.
2. Peremptory Norms (Jus Cogens)
Not all international laws are equal. Jus cogens norms are super-norms from which no derogation is permitted. A treaty that conflicts with a jus cogens norm (e.g., a treaty to coordinate a slave trade) is void ab initio.
Core Examples: Prohibitions on genocide, torture, racial discrimination, and the unlawful use of force.