International law differs from state legal systems in that it applies primarily, but not exclusively, to countries rather than individuals, and operates largely by consent, since there is no universally accepted authority to impose it on sovereign states. Therefore, states can choose not to respect international law and even violate a treaty. [5] However, such violations, particularly of customary international law and peremptory norms (jus cogens), can be countered by coercive measures ranging from military interventions to diplomatic and economic pressure. In the European Middle Ages, international law was primarily concerned with the purpose and legitimacy of war, seeking to determine what constituted a “just war.” For example, the armistice theory states that the nation that provoked an unjustified war could not enjoy the right to receive or win trophies that were legitimate at the time. [20] The Greco-Roman concept of natural law was combined with religious principles by the Jewish philosopher Moses Maimonides (1135-1204) and the Christian theologian Thomas Aquinas (1225-1274) to create the new discipline of “international law,” which, unlike its eponymous Roman predecessor, applied natural law to relations between states. A similar framework was developed in Islam, in which international law derived in part from the principles and rules set forth in treaties with non-Muslims. [21] The above cases are general rules of interpretation which do not preclude the application of specific rules for certain areas of international law. The United Nations Commission on International Trade Law is one of the principal legal bodies of the United Nations system in the field of international trade law, with universal membership, specialized in trade law, focused on the modernization and harmonization of the rules governing international trade. The UNCITRAL secretariat has established a system of jurisdiction for UNCITRAL texts (CLOUT on UNCITRAL texts) to collect and disseminate information on court decisions and arbitral awards relating to conventions and model laws resulting from the work of the Commission. The natural law approach holds that international norms should be based on axiomatic truths. The 16th writer of natural law Francisco de Vitoria In the nineteenth century, professor of theology at the University of Salamanca studied the issues of just war, Spanish authority in the Americas and the rights of Native Americans.
Since international law exists in a legal environment without a global “sovereign” (i.e. an external power capable and willing to uphold international norms), the “application” of international law is very different from the domestic context. In many cases, the application takes on coasic characteristics when the standard is self-applied. In other cases, deviating from the norm can pose a real risk, especially if the international environment changes. If this happens, and if enough States (or enough powerful States) constantly ignore a particular aspect of international law, the norm may in fact change according to the concepts of customary international law. Thus, unrestricted submarine warfare before World War I was considered a violation of international law and allegedly a casus belli for the United States` declaration of war on Germany. During World War II, however, the practice was so widespread that during the Nuremberg trials, charges against German Admiral Karl Doenitz for ordering unrestricted submarine warfare were dropped, even though the activity was a clear violation of the Second London Naval Treaty of 1936. The law of the sea, economic law, diplomatic law, environmental law, human rights law and humanitarian law are part of international law. Ancient Greece, which developed fundamental notions of governance and international relations, contributed to the formation of the international legal system; many of the earliest documented peace treaties were concluded between Greek city-states or with neighbouring states.
The Roman Empire created an early conceptual framework for international law, jus gentium (“law of nations”), which governed both the status of foreigners living in Rome and the relations between aliens and Roman citizens. The Romans adopted the Greek concept of natural law and considered ius gentiumas universal. Unlike modern international law, however, Roman international law applied to relations with and between foreign individuals rather than to political entities such as states. The term international law was coined by the English philosopher Jeremy Bentham. He defined it as “a set of rules governing relations between States”, this definition does not include the two important elements, showing how much international law has evolved today. They are individuals and international organizations. Spain, whose world empire was founded in the 16th and 17th centuries. The golden age of economic and intellectual development made an important contribution to international law. Francisco de Vitoria (1486-1546), which dealt with Spain`s treatment of indigenous peoples, invoked international law as the foundation of their inherent dignity and rights and articulated an early version of the sovereign equality of peoples.
Francisco Suárez (1548-1617) emphasized that international law is based on natural law. The field of international law covers a wide range of issues of international concern, such as human rights, disarmament, international crime, refugees, migration, nationality issues, treatment of prisoners, the use of force and war. The law of the sea is the area of international law that governs the principles and rules governing the relations between States and other entities in ocean affairs. [33] It covers areas and issues such as navigation rights, marine mineral rights and the jurisdiction of coastal waters. Maritime law differs from Admiralty law (also known as maritime law), which concerns the relations and conduct of private entities at sea.