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War and International Law

War and International Law
A Brief History of the Law of War

The roots of international law are long and ancient. Archaeologists have unearthed treaties between two Mesopotamian rulers dating back to 3100 B.C. Egyptian pharoahs also left records of treaties in effect with neighboring peoples. The ancient Chinese created what might be called international law as early as 2500 B.C. Of all ancient peoples, however, the development of modern international law owes the most to the Romans.

Pax Romana
From about 31 B.C. to the fifth century A.D., almost the entire civilized Western world was politically united under the Roman Empire. To accomplish the feat of controlling the lands conquered by its mighty armies, Rome developed a powerful central administration. Organization, military power, government and law kept the empire at relative peace and so the whole era has been called Pax Romana (Pax means peace in Latin).

To administer justice to diverse peoples, the Romans needed laws that reflected the needs of the empire. Roman judges had to settle disputes among people with different beliefs and languages. To do this, the Romans borrowed from Greek philosophers and applied what has been called “universal law.” It is based on the idea that there is a law that applies to all humans regardless of their culture or origin. The Romans believed all people could discover principles of universal law through the use of reason.

On the basis of universal law, the Romans developed a system of law called jus gentium (law of nations). It was international law used throughout the empire. The power of Rome enforced the law.

The Middle Ages
With the fall of Rome and its empire, Pax Romana ended and what had been Roman Europe fell into a period of upheaval and political instability. Threatened by foes from the north and east, people looked for protection by forming alliances on the local level. These unstable political conditions gave rise to the early versions of feudalism, with kings and nobles exercising control over relatively small areas. The local population swore loyalty to a noble or king in exchange for protection and security. During this period, people sought a stabilizing force for bringing order to what, in comparison to Pax Romana, must have seemed a brutal and chaotic time. Of all the institutions of the Middle Ages, the Roman Catholic Church offered the best chance to fulfill the role once held by Rome. It could provide a moral voice, even if it were unable in any ongoing way to provide the military and political muscle to impose order.

In addition, drawing on Greek and Roman ideas, medieval philosophers contended that there existed a body of legal principles and a sense of right that applied to all peoples everywhere. they called this “natural law.” Its rules could be discovered through the processes of pure reasoning. In effect, natural law existed “in the air,” merely waiting for the embrace of right-thinking men, no matter what their position in life might be. In addition, since the church’s law applied to all Christians, it too had an international force. The sanctity of treaties, the right to make war, and arbitration of disputes all came under the authority of the pope.

In this era, Christian theologians such as Saint Augustine of Hippo, and later St. Thomas Acquinas, developed ideas about what made a war just or unjust. Augustine argued that only legitimate rulers could make war and that it must be fought for the right reasons, mainly the desire to bring about peace. Aquinas built on the ideas of Augustine. He held that war could only be just if three conditions were met. A war must be waged by a lawful authority with the power to wage war. A war must have a just cause. A war must be intended to accomplish good or avoid evil. These concepts had great influence on later thinkers.

The Early Modern Era
The Thirty Years War ushered in a new era. What began as a religious feud among medieval societies ended with the birth of modern states. The Roman Catholic Church and its Holy Roman Empire became less important in political affairs. To meet the new realities, the doctrine of sovereignty developed. It held that the highest authority possible rested in the hands of the heads of theoretically equal states. Each monarch, within his or her domain, held the mantle that once cloaked popes and Roman emperors.

Although the notion of sovereignty did address the new political reality in Europe, it also raised some thorny questions. If no higher authority than that of individual states existed, what authority could regulate them domestically or internationally? If quarrels arose among them, who would settle them? Would mankind face a cycle of endless war with nothing to determine who was right or wrong? Certainly, each monarch was answerable to his own god, through the divine right of kings, but what if the same god gave different messages? The first hint of an answer, philosophically at least, came from the work of Hugo Grotius and other thinkers.

Grotius, a 17th century Dutch scholar, again approached the problem of war. Like Augustine and Aquinas before him, he argued that wars were “just” or “unjust.” Unlike his Christian predecessors, he based his theories on the ideas of the Enlightenment. He identified factors such as the motivation of the states and the cause involved to judge whether a war was “just” or “unjust.” More importantly, he argued for the principle that the actions of states were not above law. Instead, just as individuals were bound by a natural law, so were states. From this early “law of nations” evolved some of our modern ideas about international law.

The Concert of Europe
Essential to the political system between 1818 and 1914 was the concept of the balance of power. After the Napoleonic Wars, the Europeans set up the Concert of Europe. Using alliances, they aligned themselves so that no group of nations was clearly militarily stronger than any other group of nations. By balancing the power between groups, stability was reached and all-out wars were avoided for almost a hundred years. Because of the resulting political stability on the continent, Europe was able to dictate policy to the rest of the world. International politics, and for that matter laws, became Europeanized in a way never before possible. Nations outside of Europe often found themselves at a political and legal disadvantage when dealing with European powers.

 At the same time, the rise of nationalism fostered the emergence of the concept of consent. The European nations held fast to the belief that no state, at least no powerful state, was responsible to any higher authority than itself. The applicability of international law became limited to situations in which a state agreed to limit its options through treaty, accord, or international agreement.

Ultimately, the Concert of Europe, relatively stable for so long, failed when the European powers found themelves dragged into the First World War by their entangling alliances.

Collective Security
The 20th century saw two attempts to bring world order through the use of international organizations, the League of Nations and the United Nations. In both cases, membership was extended to nations all over the world. Both were designed to be a forum for settling international conflict, a source for international law, and to provide a peacekeeping function through collective security. Under collective security, nations give up the use of force in international disputes and pledge to come to the aid of nations who are attacked by aggressors. In both cases, problems arose in defining “aggression” and in getting member nations to agree to act. The rule of law could not escape the reality of politics.

Until the fall of the Soviet Union and its Warsaw Pact of Eastern European vassal states, collective security operated under the realities of a bipolar world. The United States and its allies countered the Soviet bloc. The threat of mutually assured destruction by each bloc’s nuclear weapons promoted rough political stability throughout the Cold War. Both of the superpowers had veto powers over the use of the collective security powers of the Security Council of the United Nations. The U.N. could intervene only when both superpowers agreed. (In one notable exception, the Security Council voted to send forces to counter northern aggression in the Korean Conflict after the Soviet representatives had walked out in protest.)
With the end of the Cold War, only one superpower remained. Questions arose about the role of the alliances and collective security arrangements that had been built up to address the needs of a bipolar world. Further complicating the issue has been the increase of worldwide terrorism. Terrorist groups are not nation states and they operate across national borders. As such, many of the assumptions of collective security and laws among nations do not apply. Since the terrible destruction stemming from the events of September 11, 2001, the United States under the Bush administration has been grappling with a different world reality. How this will affect existing institutions and doctrines of international law remains to be seen.

For Discussion and Writing
l. Many scholars argue that international law is mainly the product of Western thinking. What evidence can you find in the brief history that supports this argument?

2. Who was Hugo Grotius? Why was he important?

3. Do you believe there are universal or natural laws? If so, what are they?

4. What is a “just war?” With which of the definitions in the reading do you most agree? Why?

5. Does a country ever have the right to ignore international law or act outside the United Nations collective security process? If so, under what circumstances?

The International Law of War Commission

Imagine you have been appointed to an international commission. Its mission is to study the issue of a “just war” and make recommendations about a definition of it for the 21st century. To complete your task, follow these steps:

1.     Divide into groups of three or four students and appoint a chairperson to lead your discussions and a spokesperson to give your report to the whole commission.

2.     Review the material in the reading about previous definitions of a just war including the work of St. Augustine, St. Thomas Aquinis and Hugo Grotius. Also, review the material concerning collective security.

3.     Conduct a discussion using these questions:

  • What are legitimate reasons for a just war? (For example, self-defense or immediate threat of attack)

  • What goals must a country have to conduct a just war? (For example, to create stability in a region or gain lost territory.)

  • Must a just war be approved by the United Nations or some other international body? Why or why not?

  • Is a just war ever possible? Why or why not?

4.     Prepare a statement describing the elements necessary for a just war and prepare to present it to the entire commission.

5.     Present your recommendations and answer any questions other commission members may have.

6.     Discuss and choose the best ideas presented by all the groups and create a commission recommendation.