In his book International Law (Cassese, A. (2005). International law. Oxford: Oxford University Press.), Antonio Cassese identifies four significant periods of development of modern international law. These four periods generally correspond to technological and socio-political evolution and are restricted by major wars.
The Peace of Westphalia to World War I
The era from the Peace of Westphalia (1648) to the start of the First World War was one of the developments of the modern nation-state. Before 1648, many countries did not have effective centralized governments, government bureaucracies, or legal enforcement. The period after 1648 saw the development of the current central government, with bureaucrats and a bureaucratic structure replacing the dispersed fiefdoms and local rule of the nobility.
This evolution in governance was also brought on by the European powers’ rapid expansion of colonial expansion throughout the world, fueled by the Industrial Revolution. The Industrial Revolution in Europe and the United States created a technological gulf between the major powers and the rest of the world and an insatiable hunger for raw materials and labor. While some of the subjugated areas subsequently gained their independence in the late Eighteenth and Nineteenth Centuries, particularly in the Americas, this period saw the colonial subjugation of vast areas of Asia (India, the Philippines, Indonesia, Australia, and Chinese trading ports), Africa, and the Americas. To both administer these territories and develop methodologies for resolving disputes globally, the dominant world powers began to rely more heavily on the principles of formalized international law.
International law during this period was one of the dominant European/American powers broadly interacting with each other as equals and treating the remainder of the world as inferior powers. Using capitulation agreements created extraterritorial extensions of domestic powers in foreign lands. These agreements, executed between European powers and the rest of the world, subjected European and American citizens to the laws of their home country rather than those of the host nation. These treaties allowed European and American citizens to be considered “above the (local) law” in much of the world.
As a practical matter, there was no dominant superpower or duopoly. The major powers (the US, Spain, France, Portugal, Britain, Russia, Sweden, the Netherlands, Austria, and Prussia) shared dominance and rivalries. Wars among this group and their related states were common.
Attempts to stabilize relations between powers and resist revolutionary tendencies after the US and French upheavals resulted in the development of the Concert of Europe – a series of treaties executed around 1815. The key elements included:
- A Declaration of Principles binding the signatories to standards of behavior that were based on the precepts of Christian Religion
- A military alliance based on the Treaty of Paris (1815) between Austria, Prussia, Russia, and France (1818). The purpose was to provide mutual aid to suppress any revolutionary elements and prevent the renewal of the revolutionary movements that led to the American and French Revolutions.
- Periodical summit meetings. The rise of multilateral diplomacy and regular meetings of nations were common concerns and interests that could be discussed and ideally settled.
The emergence of the US somewhat limited its effectiveness as a world power and the promulgation of the Monroe Doctrine in 1823, which provided that while the US would not intervene in European colonial affairs, the US would not tolerate European intervention in the affairs of independent states in the Americas.
The major powers of the era set the parameters of international law and generally framed up the tenets of Christian principles. Development of laws around the treatment of diplomats, the use of force between powers, the intervention of nations in protecting national interests in commercial ventures, and laws of navigation and the high seas.
The codification and development of dispute resolution procedures began shifting the elements of power from the major powers to a more balanced approach. The adoption of the Hague Convention of 1899, among other treaties of the period, limited the ability of powers to use certain types of weapons and dictated the treatment of combatants. Importantly, these treaties governed the interactions between signatories but left the colonial and non-European nations unprotected.
Following belligerent actions in China and South America to collect reparations, two Argentines moved to change the status quo and level the playing field between the major colonial powers and the rest of the world. C. Calvo (1824-1906) was an Argentine jurist who developed the Calvo Doctrine. The Calvo doctrine (c.1870) provided for the supremacy of local law over the prior practice of capitulation agreements. Calvo pressed to have these provisions included in natural resource concession contracts. The second was Luis Maria Drago (1859-1921), the Argentine Foreign Minister, who argued that foreign powers should not have the right to use war as a recourse to secure the payment of sovereign debt. This doctrine found its way into the 1907 Hague Convention but was not ratified by any European power.
This period saw the development of the basic tenets of international law, the evolution of multilateral diplomacy, and the beginning of the leveling of powers between considerable powers and small nations. The foundations were set for the future development of international law – following one of the most devastating wars in history.
World War I to World War II
World War I marked both the failure of international diplomacy and the end of the colonial period. Colonial expansion largely ceased, and the monarchies of Europe came under increasing pressure – with many (Germany, Austria, Russia, the Ottoman Empire, and Spain) being eliminated in revolutions and post-war treaty demands. This era also eliminated many of the remaining capitulation agreements and the gradual return of local enforcement of laws.
With some 17 million military and civilian deaths, the war also brought a united desire to utilize diplomacy and the rule of law instead of forcing arms to dictate international relations. The rise of transportation and weapons technology made trade and warfare easy to conduct on a global scale. Additionally, the rise of the USSR after the Russian Revolution led to the emergence of an anti-capitalist ideology that would disrupt the historical balance of power on both an economic and ideological front.
Following the First World War, the belligerents developed a framework for diplomacy and enforcement of international law through the League of Nations. However, the failure of the US and USSR to enter into the League served to limit its effectiveness and ultimately led to its failure. In addition to the lack of participation by several of the major powers, the organization proved itself to be ineffective when dealing with conflicts like Italy’s dispute with Greece and the occupation of Corfu (1929) and the Italian invasion of Ethiopia (1935) or the Japanese invasion of Manchuria (1933) due to a lack of enforcement power.
The Permanent Court of International Justice (PCIJ), set up in 1921, served to arbitrate disputes between nations and generally worked well – delivering about 60 opinions and decisions during its operation. The scope of disputes ruled on by the PCIJ and other tribunals was wide-ranging and served to begin to establish a working international law system, along with enforcement ability. This resulted in formalizing the dispute resolution process and establishing a precedent for resolving disputes.
The Cold War
The period after World War II saw international law take center stage. The war crimes trials and the establishment of the United Nations in 1945-46 provided mechanisms and the practical implementation of international law globally. Rather than focusing on reparations against the Axis powers, individuals were identified and tried for their crimes. A formal structure for the resolution and discussion of major international issues, the United Nations, was established with the participation of all major world powers.
Two superpowers, the United States and the USSR, arose after the war. These two superpowers represented competing for military, legal, political, and economic polarities that soon divided much of the globe into two opposing camps.
This period also saw the broad elimination of colonialism worldwide, as dozens of states regained their independence, and the influence of European powers began to fade. Faced with varying degrees of readiness – both political and economic – these new nations relied on international law and organizations for development assistance, ensuring a level playing field with the global superpowers and now representing a majority of the nations in the world – both in terms of population and number of countries.
The socialist states in the UN pushed to drive self-determination and racial equality during this period. They used the overwhelming number of new nations in the UN General Assembly to make strides in that arena. The UN Covenants on Human Rights and the UN Declaration on Friendly Relations, and the UN New International Economic Order began establishing a legal framework of rules and objectives to protect and enhance developing nations.
Post-Cold War Period
After the fall of the USSR in 1989, the United States effectively became the sole superpower and assumed the mantle of international “policeman.” Interventions by the United States, with and without UN support, in Kosovo, Bosnia, Somalia, Iraq, and Afghanistan during the last 20 years supported the view of the US as the world hegemon.
As a result of the disproportionate power exercised by the US and the emergence of a regional political and central economic government in Europe through the EU, the UN has seen its influence and impacts diminish over the last 25 years. There continues to be a move to globalization, which is being resisted at the national level. The recent vote by the UK to leave the EU is a sign that perhaps the highly structured enforced international governance approach represented by the EU may not be embraced by sovereign states.
The Cold War saw tension between East and West, and the post-Cold War era is seeing international law conflict emerging between North and South – the developed and the developing nations. These tensions, which have their seed in the colonial period, have become more pronounced as Northern nations focus on environmentally conscious and sustainable development, limiting access to cheap but environmentally damaging technology for emerging nations.
One emerging trend in the post-Cold War period is integrating multiple bodies of law in treaties and agreements. Historically, a treaty or trade agreement focused on one element: human rights, environmental protection, weapons limitations or tariffs, and trade. However, the new trend balances these formerly separate and often conflicting elements into holistic and integrated agreements.
The evolutionary trend of international law appears to be headed towards broader agreements, regionalization, and more robust enforcement methodology. While the recent vote by the UK to leave the EU is a break in this trend, I believe a look at the long-term trend and history of international law leads one to conclude that this is a “speed bump” on the road toward further globalization and legal integration and standardization.