The rights accorded to states under international law imply responsibilities. States are liable for breaches of their obligations, provided that the breach is attributable to the state itself. A state is responsible for direct violations of international law—e.g., the breach of a treaty or the violation of another state’s territory. A state also is liable for breaches committed by its internal institutions, however they are defined by its domestic law; by entities and persons exercising governmental authority; and by persons acting under the direction or control of the state. These responsibilities exist even if the organ or entity exceeded its authority. Further, the state is internationally responsible for the private activities of persons to the extent that they are subsequently adopted by the state. In 1979, for example, the Iranian government officially supported the seizure of the U.S. embassy by militants and the subsequent holding of diplomats and other embassy staff as hostages. A state is not internationally responsible if its conduct was required by a peremptory norm of general international law, if it was taken in conformity with the right to self-defense under the UN Charter, if it constituted a legitimate measure to pressure another state to comply with its international obligations, if it was taken as a result of a force majeure (French: “greater force”) beyond the state’s control, if it could not reasonably be avoided in order to save a life or lives, or if it constituted the only means of safeguarding an essential interest of the state against a grave and imminent peril, where no essential interest of the states toward which the obligation exists (or of the international community) was impaired.

A state must make full reparation for any injury caused by an illegal act for which it is internationally responsible. Reparation consists of restitution of the original situation if possible, compensation where this is not possible, or satisfaction (i.e., acknowledgment of and apology for the breach) if neither is possible.

One controversial aspect of international law has been the suggestion, made by the International Law Commission in its 1996 draft on State Responsibility, that states can be held responsible for “international crimes” (comprising internationally wrongful acts resulting from the breach by a state of an international obligation so essential for the protection of the international community’s fundamental interests that its breach is recognized as a crime by that community). Examples given included aggression, colonial domination, and genocide. In addition to the argument that states (as distinct from individuals) could not be guilty of crimes as such, serious definitional problems arose, and there was concern over the consequences of such crimes for states. Accordingly, in its draft articles finally adopted in 2001, the International Law Commission dispensed with this politically divisive approach but retained the idea of a more serious form of international wrong. The commission emphasized the concept of serious breaches of obligations arising under a peremptory norm of international law (i.e., the rules of jus cogens, or those deemed essential for the protection of fundamental international interests). In such circumstances, all states are under an obligation not to recognize such a situation and to cooperate in ending it.

States may take up the claims of individuals injured because of the acts or omissions of another state. In such circumstances, the injured persons must have exhausted all domestic remedies to hold the state responsible unless these are ineffective. Further, the injured person must be a national of the state adopting the claim. Although states alone possess the right to grant nationality, if the claim is pleaded against another state, the grant of nationality must conform to the requirements of international law and, in particular, demonstrate the existence of a genuine link between the individual and the state concerned.

Territory

The sovereignty of a state is confined to a defined piece of territory, which is subject to the exclusive jurisdiction of the state and is protected by international law from violation by other states. Although frontier disputes do not detract from the sovereignty or independence of a particular state, it is inherent in statehood that there should be a core territory that is subject to the effective control of the authorities of the state. Additional territory may be acquired by states through cession from other states (the Island of Palmas case in 1928); by the occupation of territory that is terra nullius (Latin: “the land of no one”)—i.e., land not under the sovereignty or control of any other state or socially or politically organized grouping; or by prescription, where a state acquires territory through a continued period of uncontested sovereignty.

Under the UN Charter, sovereign title to territory cannot be acquired purely and simply by the use of force. Express or implied consent is required under international law for recognition of territory acquired by force, whether or not the use of force was legal. When states are created from the dissolution or dismemberment of existing countries, it is presumed that the frontiers of the new states will conform to the boundaries of prior internal administrative divisions. This doctrine, known as uti possidetis (Latin: “as you possess”), was established to ensure the stability of newly independent states whose colonial boundaries were often drawn arbitrarily.

Maritime spaces and boundaries

The sovereign territory of a state extends to its recognized land boundaries and to the border of airspace and outer space above them. A state that has a coastal boundary also possesses certain areas of the sea. Sovereignty over bodies of water is regulated by four separate 1958 conventions—the Convention on the Territorial Sea and Contiguous Zone, the Convention on the Continental Shelf, the Convention on the High Seas, and the Geneva Convention on Fishing and Conservation of the Living Resources of the High Seas—and by the comprehensive Law of the Sea treaty (1982), which entered into force in 1994.

The territory of states includes internal waters (i.e., harbours, lakes, and rivers that are on the landward side of the baselines from which the territorial sea and other maritime zones are measured), over which the state has full and complete sovereignty and exclusive jurisdiction. Through the Law of the Sea treaty and now under customary international law, a state may claim a territorial sea of up to 12 nautical miles from the baselines (essentially the low-water mark around the coasts of the state concerned), though, in cases where a coast is heavily indented, a series of straight baselines from projecting points may be drawn. A state has sovereignty over its territorial seas, but they are subject to the right of innocent passage—i.e., the right of all shipping to pass through the territorial waters of states, provided that the passage is not prejudicial. Examples of prejudicial conduct include the threat or use of force, spying, willful and serious pollution, breaches of customs, sanitary, fiscal, and immigration regulations, and fishing. Coastal states may exercise a limited degree of criminal jurisdiction with regard to foreign ships that are engaged in innocent passage through their territorial seas (e.g., in cases where the consequences of the crime alleged extend to the coastal state or where such measures are necessary for the suppression of the traffic of illicit drugs).

The 1958 Convention on the Territorial Sea and Contiguous Zone provided that states cannot suspend the innocent passage of foreign ships through straits that are used for international navigation between one part of the high seas and another part of the high seas or the territorial sea of a foreign state. The 1982 treaty established a new right of transit passage for the purpose of continuous and expeditious transit in straits used for international navigation between one part of the high seas or exclusive economic zone and another. Some international straits are subject to special regimes. The controversial Straits Question, for example, concerned restrictions in the 19th and 20th centuries that limited naval access to the Bosporus and Dardanelles—which connect the Black Sea with the Sea of Marmara and the Mediterranean Sea—to countries bordering the Black Sea.

A series of other maritime zones extend beyond territorial seas. A contiguous zone—which must be claimed and, unlike territorial seas, does not exist automatically—allows coastal states to exercise the control necessary to prevent and punish infringements of customs, sanitary, fiscal, and immigration regulations within and beyond its territory or territorial sea. The zone originally extended 12 nautical miles from the baselines but was doubled by the 1982 treaty. The exclusive economic zone developed out of claims to fishing zones. The 1982 treaty allowed states to claim such a zone, extending 200 nautical miles from the baselines, in which they would possess sovereign rights to explore, exploit, conserve, and manage the natural resources of the seas and seabed; to exercise jurisdiction over artificial installations and scientific research; and to protect and preserve the marine environment. The zone was accepted as part of customary international law in the ICJ’s 1985 decision in the dispute between Libya and Malta, which concerned the delimitation of the continental shelf between them.

A state is automatically entitled to exercise sovereign rights to explore and exploit the natural resources in an adjacent continental shelf (i.e., the ledges projecting from the land into and under the sea). The shelf may extend either to the outer edge of the continental margin or to 200 miles from the baselines where the outer edge of the continental margin does not reach that distance. Thus, the continental shelf as a concept in international law becomes a legal fiction where the shelf does not in fact extend as far as 200 miles.

Problems have arisen over the delimitation of the various maritime zones between adjacent and opposing states. International law generally requires equitable resolutions of maritime territorial disputes. Although the definition of equity is unclear, relevant factors include the impact of natural prolongation of the land territory (i.e., the basic principle that the continental shelf is a continuation of the land territory into the sea), proportionality between the length of a disputing party’s coastline and the extent of continental shelf it controls, the principle of equidistance (i.e., a line of equal distance from the two shores in question), and the existence (if any) of islands between the coastlines.