International law, also known as public international law and the law of nations, is the set of rules, norms, legal customs and standards that states and other actors feel an obligation to, and generally do, obey in their mutual relations. In international relations, actors are simply the individuals and collective entities, such as states, international organizations, and non-state groups, which can make behavioral choices, whether lawful or unlawful. Rules are formal, typically written expectations that outline required behavior, while norms are informal, often unwritten guidelines about appropriate behavior that are shaped by custom and social practice. It establishes norms for states across a broad range of domains, including war and diplomacy, economic relations, and human rights.
International law differs from state-based domestic legal systems in that it operates largely through consent, since there is no universally accepted authority to enforce it upon sovereign states. States and non-state actors may choose to not abide by international law, and even to breach a treaty, but such violations, particularly of peremptory norms, can be met with disapproval by others and in some cases coercive action including diplomacy, economic sanctions, and war. The lack of a final authority in international law can also cause far reaching differences. This is partly the effect of states being able to interpret international law in a manner which they see fit. This can lead to problematic stances which can have large local effects.
