International Law

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Written By AndrewPerry

Founded in 2015 by a group of passionate legal professionals and enthusiasts, FlowingLaw started as a small blog. Today, it's a thriving community where ideas, expertise, and legal advice flow freely.





What is international law?
International law, commonly referred to as “public international law,” regulates relations and activities between nations. It also contains rules regarding the operations of international organizations, such as the United Nations. In addition, it governs state treatment of individuals and juridical persons (i.e., non-natural persons, such as a corporation, association or partnership).

International law is distinct from “private international law” (also known as “conflict of laws”), which regulates dealings between individuals and juridical persons from different nations.

Note that international law refers to nations as sovereign states. In this context, sovereign states does not mean states within a nation. Furthermore, in the United States, individual states lack authority to engage in international dealings. The U.S. Constitution explicitly denies states this power, and vests it with the federal government. (U.S. Const. Art. I, § 10).

International law encompasses several areas, such as international trade, the creation and dissolution of states, use of force (regarding when a state may initiate force against another state), armed conflict (“humanitarian law”, which regulates how a state conducts an armed conflict), human rights (which are set forth in several international instruments, such as the Declaration of Human Rights), refugees, crimes, environment, labor, the sea, air space, and postal services.

How is international law enforced?
International law differs from domestic law. In the United States, the federal and state governments enforce domestic American law. However, in terms of international law, no government or international organization enforces international law. Although the United Nations Security Council may pass measures authorizing enforcement, the enforcement entity envisioned (Art. 43) to carry out such measures never materialized due to the failure of member states to provide the necessary resources (such as troops). (An enforcement body should not be confused with existing United Nations peacekeeping forces, whose function is to maintain peace and security, not to enforce breaches of international law.)

How are international disputes resolved?
International disputes sometimes result in armed conflict between states, despite the prohibition of aggressive force (meaning, force not used in self-defense) (United Nations Charter, Art. 2. However, most disputes between states are settled peacefully. Pacific settlement is often reached by diplomatic means, whereby states voluntarily comply with international law amidst pressure from other states. Another peaceful settlement mechanism is submission of the matter by the disputing states to an international tribunal, court, or arbitration.

In special circumstances, international organizations can create binding law. Resolutions passed by the United Nations Security Council under Chapter VII of the United Nations Charter may be binding on member states. An example of such a resolution is one that orders sanctions against a state in response to a breach of international law which threatens international peace and security.

Opinions issued by international tribunals (including courts and arbitration) comprise law to the extent that they are binding upon the states-parties to the proceeding. Such decisions are not binding on non-parties, but may serve to reveal the composition of international law to other states and tribunals.