1. Core Legal Answer & Context: The statement that "International law is primarily concerned with Rights, Duties and Interests of States" accurately reflects the traditional, Westphalian view of international law, where states were considered the exclusive, or at least primary, subjects. In this classical perspective, individuals and non-state entities (NSAs) were largely seen as objects of international law, their rights and duties mediated solely through their national states. However, a critical examination reveals that this statement, while historically grounded, is an oversimplification of contemporary international law, which has undergone a profound evolution, significantly expanding the place of individuals and various non-state entities.

Traditional State-Centric View: Historically, international law was a law between states, created by states, for states. States possessed full international legal personality, meaning they could hold rights, incur duties, enter into treaties, and bring international claims. Individuals were considered subjects of national law, and any international protection or obligation they had was typically derived from their state's consent to a treaty or customary rule.

Evolving Place of Individuals: Post-World War II, the role of individuals in international law dramatically expanded:

• International Human Rights Law (IHRL): The Universal Declaration of Human Rights (1948) and subsequent treaties like the International Covenant on Civil and Political Rights (ICCPR) and the International Covenant on Economic, Social and Cultural Rights (ICESCR) directly grant rights to individuals, independent of their nationality. Individuals can, in many instances, directly invoke these rights against their own states before international or regional human rights bodies (e.g., European Court of Human Rights, UN Human Rights Committee).
• International Criminal Law (ICL): Individuals are now held directly accountable for international crimes such as genocide, crimes against humanity, war crimes, and aggression. The Nuremberg and Tokyo Trials, and later the International Criminal Court (ICC), established that individuals, not just states, bear responsibility for such grave violations.
• International Investment Law: Individuals and corporations can directly bring claims against states under bilateral investment treaties (BITs) or multilateral agreements, bypassing their home state's diplomatic protection.

Evolving Place of Non-State Entities (NSAs): Beyond individuals, various non-state entities have also acquired a significant, albeit differentiated, status in international law:

• International Organizations (IOs): Entities like the United Nations, World Trade Organization, and World Health Organization possess international legal personality, allowing them to enter into treaties, bring claims, and incur international obligations. Their powers are derived from their constituent treaties.
• Multi-National Corporations (MNCs): While generally not considered full subjects of international law, MNCs exert immense influence on international relations and law. They are increasingly subject to international norms regarding human rights, environmental protection, and anti-corruption, often through soft law instruments and corporate social responsibility initiatives. They also possess direct rights under international investment law.
• Indigenous Peoples: Recognized as having collective rights, particularly the right to self-determination and rights over their lands and resources, under instruments like the UN Declaration on the Rights of Indigenous Peoples.
• Armed Non-State Actors: In situations of armed conflict, certain armed non-state groups acquire specific duties under international humanitarian law, particularly Common Article 3 of the Geneva Conventions.
• Non-Governmental Organizations (NGOs): While typically lacking international legal personality, NGOs play a crucial role in international law-making, monitoring, advocacy, and providing expertise to international bodies.

Continuing Primacy of States: Despite these developments, states undeniably remain the primary actors and subjects of international law. They are the principal creators of international law (through treaties and customary practice), the main enforcers, and the primary parties in contentious cases before the International Court of Justice. The principle of state sovereignty and consent remains fundamental to the international legal order.

2. Relevant Statutes and Sections:

• UN Charter: Article 1 (principles of self-determination), Article 2 (sovereign equality of states).
• Universal Declaration of Human Rights (UDHR) 1948: Lays the foundation for individual rights.
• International Covenant on Civil and Political Rights (ICCPR) 1966: Grants direct rights to individuals.
• Rome Statute of the International Criminal Court (1998): Establishes individual criminal responsibility for international crimes.
• Vienna Convention on the Law of Treaties (VCLT) 1969: Governs treaties between states, highlighting state consent.
• Statute of the International Court of Justice (ICJ): Article 34(1) states that only states may be parties in contentious cases.

3. Important Landmark Cases:

• Reparation for Injuries Suffered in the Service of the United Nations (ICJ Advisory Opinion 1949): This case established the international legal personality of international organizations, recognizing their capacity to possess rights and duties under international law.
• Nuremberg Trials (International Military Tribunal 1945-46): These trials were pivotal in establishing the principle of individual criminal responsibility under international law, asserting that individuals can be held accountable for international crimes, regardless of their official capacity.

4. Clear Conclusion: While international law historically centered on states, the statement that it is primarily concerned with states' rights, duties, and interests is increasingly outdated and incomplete. The post-WWII era has witnessed a significant and irreversible shift, recognizing individuals as direct holders of rights and duties (e.g., human rights, international criminal responsibility) and acknowledging the distinct, albeit varied, legal personality and influence of various non-state entities (e.g., international organizations, corporations, indigenous peoples). Modern international law is a more complex, multi-layered system where states remain central, but share the stage with a growing array of other actors, reflecting a more nuanced and inclusive global legal order.