The outlaw of war and armed conflict: from the League of Nations to the United Nations

The outlaw of war and armed conflict: from the League of Nations to the United Nations

War became a part of human society a long time ago, and for many centuries it dominates historical records. War and peace perpetually alternate and that peace is always an endless project. The existence of a peace treaty is clear evidence that the total triumph of peace over conflict has not still occurred and that peace is always in a state of project and perspective. 

During the XIXth century outstanding endeavours were undertaken by the international community to limit the suffering caused to the wounded military personnel on the battlefields and to alleviate its effects. In 1864 the first treaty on the protection of military victims of warfare was drawn up and signed in Geneva. All treaties and covenants on international humanitarian law later adopted throughout the XXth century were not focused on the real problems caused by armed conflicts or the multiple issues raised by war, but only in those rules needed to bring a better protection for the vulnerable victims of warfare.

In 1899 the so-called “The Peace Conference”, which took place at the Hague, adopted several important Conventions and Declarations with the aim of strengthening the international mechanisms aimed to promoting the pacific settlement of disputes, the regulation of the laws and customs of war by land, the maritime warfare or the prohibition of some special projectiles, explosives and bullets. Afterwards, the second conference, held again at the Hague in 1907, adopted thirteen treaties and also did prefigure later 20th-century attempts at international cooperation. 

The Hague Conventions of 1899 and 1907 continue to stand as symbols of the need for restrictions on war and the desirability of avoiding it altogether. After World War II, the judges at Nuremberg Trials found that by 1939, the rules laid down in the 1907 Hague Convention were recognized by all civilized nations and were regarded as declaratory of the laws and customs of war.

On 28 June 1919 the Peace Treaty of Versailles was signed as a conclusion of World War I. In accordance with its Preamble, the promotion of international co-operation and the achievement of peace and security in the world should be achieved by the following means: firstly, the acceptance of obligations not to resort to war; secondly, the prescription of open, just and honorable relations between nations; thirdly, the firm establishment of the understandings of international law as the actual rule of conduct among Governments; and fourthly, the maintenance of justice and a scrupulous respect for all treaty obligations. In addition, it was recognized in its article 8, in the line of the first Hague Conference of 1899, that “… the maintenance of peace requires the reduction of national armaments to the lowest point consistent with national safety and the enforcement by common action of international obligations”. 

The Preamble of the Covenant of the League of Nations is still far from banning absolutely the phenomenon of war. The drafters of the Covenant of the League did not dare to condemn all wars, because they still conceived war as a means to reach other political interests. The right to war was recognized and regrettably legitimized in only certain cases in the Covenant. 

The Covenant only imposes the Member States to respect the following obligations before resorting to war, namely: submission of the dispute to arbitration or inquiry to the Council, establishment of a Permanent Court of International Justice or good offices by the Secretary General. In the case that some Member decides to resort to war in disregard of the previous provisions, then the League shall ipso facto condemn them for having committed an act of war against all other Members of the League. 

On 16 January 1920, the birth of the new world will be recorded in history, because the League of Nations held its first session and definitively substituted the reign of force by the rule of law. 

On 16 October 1925, several nations adopted the Treaty of Mutual Guarantee or the so-called Locarno Pact by which they mutually undertook in its article 2 that they will in no case attack or invade each other or resort to war against each other, with the exception of the following situations, namely: the right of legitimate defence, an action taken in pursuance of Article 16 of the Covenant of the League of Nations or an action as the result of a decision taken by the Assembly or by the Council of the League of Nations. 

The renunciation of war as an instrument of national policy was successfully banned for the first time in history in 1928 thanks to the efforts made by the Foreign Ministers of France and Unites States of America. Signatory states of the famous Briand-Kellogg Pact promised not to use war to resolve disputes or conflicts. Since this agreement was concluded outside the League of Nations, it still remains a binding treaty under international law. Indeed, the treaty is perpetual as it contains no clause of limitation, no provision for determination or denunciation. It follows that the condemnation of war as a legal provision is currently in force and it should take therefore into consideration by the international community.  

The Pact against war is one of the shortest international treaties in the contemporary diplomatic history. It is composed only by two main dispositions, the condemnation of war (art. 1) and the obligation of States to settle their disputes by peaceful means (art. 2). The selfish and voluntary war was totally outlawed by this international agreement. Nevertheless, in accordance with the treaty, the use of force would be only possible in case of self-defense and between those States signatories and no-signatories of the treaty. After its final adoption, sixty countries adhered to the treaty, which demonstrates that the peace hopes in that time were deeply rooted in the world.      

In order to create a more peaceful world, the Charter of the United Nations established in its article 1 and 2 the following “purposes and principles”, inter alia: the prohibition of acts of aggression or other breaches of the peace, the development of friendly relations among nations, the self-determination of peoples, the enhancement of international co-operation, the promotion of human rights and fundamental freedoms, the settlement of international disputes by peaceful means, the prohibition of threat or use of force against the territorial integrity or political independence of any state. These principles codified in the previous articles of the Charter constitute the basic foundational principles of the whole body of international law. 

The Purposes and principles of the UN Charter have been expressly included in the Declaration on Preparation on Societies to Life in Peace of 1978, the Declaration on the Right of Peoples to Peace of 1984 and the Declaration on a Culture of Peace of 1999.  In addition, all these peace laws strongly demanded that the policies of States be directed towards the elimination and eradication of war, the prohibition of propaganda for war and disarmament. 

The Charter of the United Nations states clearly that the threat or use of force against other States is unlawful. Since 1945, war has no longer been an acceptable way to settle differences between States. However, the Charter has not completely outlawed the use of force. Indeed, States retain the right to defend themselves, individually or collectively, against attacks on their independence or their territory, in response to a (legal or illegal) use of force. The Charter's prohibition of the use of force does not encompass internal armed conflicts (or civil wars). Chapter VII of the Charter allows Member States to use force in collective action to maintain or restore international peace and security.

Taking into account that in a situation of armed conflict, fundamental freedoms are gravely violated, then the Parties in conflict should respect the main ratified international human rights instruments during the military confrontation, as set out in the UNGA resolution 66/99 on effects of armed conflicts on treaties of 27 February 2012.

The international community has always elaborated international rules which limit the effects of war. In the latest years, civil society movements have promoted the adoption of important legal instruments aimed to protecting the population in a context of warfare and also limiting the trade and use of certain arms. 
Nowadays the international community has the legal resources to eliminate progressively war and armed conflicts over the earth through the respect of international law, the promotion of the culture of peace and the friendship among all peoples and nations. 

David Fernandez Puyana, PhD, LLM and MA