This statement accurately reflects a fundamental principle of modern international law concerning jus cogens, or peremptory norms. Jus cogens represents a higher category of international law norms from which no derogation is permitted, and any treaty or customary rule conflicting with them is considered void.

What is Jus Cogens (Peremptory Norms)? Jus cogens (Latin for 'compelling law') refers to a body of fundamental principles of international law that are accepted and recognized by the international community of states as a whole as norms from which no derogation is permitted. These norms are considered so fundamental to the international legal order that they cannot be set aside by treaty or custom.

Key Characteristics of Jus Cogens:

1. Non-Derogable: This is the defining characteristic. States cannot, by treaty or any other agreement, contract out of their obligations under jus cogens.
2. Universal Acceptance: A norm becomes jus cogens only if it is accepted and recognized by the international community of states as a whole.
3. Hierarchical Superiority: Jus cogens norms occupy the highest position in the hierarchy of international law, overriding all other sources of international law (treaties, customary law, general principles) that conflict with them.
4. Evolving Nature: While fundamental, the list of jus cogens norms is not static and can evolve over time as the international community develops new fundamental values.

Constitutional Basis (Vienna Convention on the Law of Treaties - VCLT): The concept of jus cogens is codified in the Vienna Convention on the Law of Treaties (VCLT), 1969, which is widely considered the 'treaty on treaties':

• Article 53 (Treaties conflicting with a peremptory norm of general international law): "A treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law. For the purposes of the present Convention, a peremptory norm of general international law is a norm accepted and recognized by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character."
• Article 64 (Emergence of a new peremptory norm of general international law): "If a new peremptory norm of general international law emerges, any existing treaty which is in conflict with that norm becomes void and terminates."

Implications for Treaties:

1. Void Ab Initio (Article 53): If a treaty is concluded and, at the time of its conclusion, it conflicts with an existing jus cogens norm, that treaty is automatically void from its inception (ab initio). This means the treaty never had any legal force or effect.
2. Termination of Existing Treaties (Article 64): If a new peremptory norm of general international law emerges after a treaty has been concluded, any existing treaty that conflicts with this newly emerged jus cogens norm becomes void and terminates from the moment the new norm is established. This highlights the dynamic nature of jus cogens.

Examples of Jus Cogens Norms: While there is no exhaustive list, widely accepted examples of jus cogens norms include:

• Prohibition of genocide.
• Prohibition of slavery and slave trade.
• Prohibition of torture.
• Prohibition of aggression (the unlawful use of force).
• Prohibition of racial discrimination and apartheid.
• The right to self-determination.

Comment: The principle that a treaty is void if it conflicts with jus cogens is a cornerstone of modern international law. It signifies a crucial shift from a purely consent-based system, where states could agree to almost anything, to a more value-oriented legal order. It imposes a fundamental limitation on the absolute freedom of states to contract treaties, reflecting the international community's commitment to certain non-negotiable, fundamental values and principles.

This doctrine ensures that states cannot use treaties to legitimize or engage in practices that are universally condemned as morally repugnant or fundamentally destructive to the international legal order. It provides a powerful tool for upholding human dignity, international peace, and security, even in the face of state sovereignty. While the precise identification of all jus cogens norms can sometimes be debated, the concept itself is firmly established and serves as a vital safeguard against agreements that would undermine the very foundations of a just international society.