Why was the Kellogg-Briand Pact of 1928 a Watershed in the Evolution of Public International Law?

By Yoav J. Tenembaum

Published on May 15, 2021

By the Kellogg-Briand Pact, officially known as the General Treaty for Renunciation of War as an Instrument of National Policy, sixty-two countries, representing most of the sovereign states in the international system at the time, pledged themselves to renounce war as “an instrument of national policy in their relations with each other.” The Kellogg-Briand Pact was initially signed in 1928 by fifteen countries.

The Kellogg-Briand Pact was seen by contemporaries as a milestone in the history of international relations. With hindsight, this article argues that it can also be deemed to be a turning point.

Historic pact

It all started in 1927 with a diplomatic initiative by France’s Foreign Minister, Aristide Briand, who proposed to his United States counterpart, Frank B. Kellogg, to sign a bilateral agreement stipulating that neither country would resort to war with each other and that any dispute would be settled by peaceful means. Kellogg responded by suggesting that such an agreement should be expanded into a multilateral pact, involving other countries as well, which Briand consented to. What began as a French initiative directed at the United States, ended up as an international pact, finally signed by most sovereign states in the world.

This was to be the first time in which the international community, or at least an overwhelming majority of it, officially and publicly committed itself to renounce war as an instrument of state. The League of Nations, set up in the wake of World War I, had already delineated legal limits to the resort to war, but had not called on member states to renounce it altogether.

According to the League of Nations Covenant, a three-month transition period would have to elapse before member states involved in a dispute were to be allowed to resort to the use of force, and that only after first having exhausted non-violent means to solve it.

As the late Professor Wilhelm G. Grewe, a former West German diplomat and an expert in public international law, would put it in his comprehensive work The Epochs of International Law: “The abandonment of the sovereign right of war through the procedural provisions of the League of Nations Covenant would bring about a certain restriction and constriction of war and, through the 1928 Kellogg-Briand Pact, its moral and legal outlawry as well.”

The Kellogg-Briand Pact was to wield a direct influence on the development of public international law. Its echo was to resound through the chambers of international diplomacy for many years to come.

The Stimson Doctrine, enunciated by the US Secretary of State, Henry Stimson, on 7 January 1932, following the Japanese invasion of Manchuria in 1931, which became an integral part of public international law, made it clear that the Japanese occupation of Manchuria would not be recognized as it resulted from an illegal act, contrary to the Kellogg-Briand Pact of 1928.

It was subsequently reinforced by a resolution of the Assembly of the League of Nations that League Members should not recognize any situation, treaty or agreement brought about by means contrary to the League’s Covenant or the Kellogg-Briand Pact. This has evolved into the principle in public international law that “legal rights cannot derive from an illegal situation (Ex injuria jus non oritur).”

The Atlantic Charter, which was signed by US President Franklin D. Roosevelt and British Prime Minister, Winston Churchill, on 14 August 1941, and was to become the diplomatic and conceptual basis for the future establishment of the United Nations, stressed that both leaders “believe that all of the nations of the world for realistic as well as spiritual reasons must come to the abandonment of the use of force.”

At a subsequent conference held in Washington D.C. on 1 January 1942, twenty-six governments then at war with the Axis Powers, declared their adherence to the principles of the Atlantic Charter, including the reference aforementioned on the use of force.

The United Nations Charter (Article 2, Paragraph 4) stipulates that “all Members shall refrain […] from the threat or use of force against the territorial integrity or political independence of any state or in any other manner inconsistent with the Purposes of the United Nations.”

To be sure, the UN Charter went beyond the Kellogg-Briand Pact as it referred not only to war, but also to all kinds of armed force, including the mere threat of its use.

Several signatories of the Kellogg-Briand Pact, including the United States and Britain, had presented diplomatic notes prior to the Pact’s ratification, indicating that wars in self-defence would be deemed acceptable.

Controversial provisions

The question that could be posed, of course, is why was not the reference to wars of self-defence mentioned in the Pact itself?

Kellogg himself, who was awarded the Nobel Peace Prize in 1929, explained that the right of self-defence was obvious and that therefore there was no need to mention it explicitly in the Pact. The right of self-defence, he emphasized, “is inherent in every sovereign state and is implicit in every treaty.” Furthermore, he went on to elaborate that the consequent need to define terms such as “self-defence” and “aggressor” would be almost impossible to achieve. “It is not in the interest of peace that a treaty should stipulate a juristic conception of self-defence, since it is far too easy for the unscrupulous to mould events to accord with an agreed definition.” The Pact, Kellogg stressed, did not prohibit the right of the signatories to defend themselves with force if necessary.

The Kellogg-Briand Pact was criticized for not having proposed any enforcement mechanism to prevent its violation (see, for instance, Henry Kissinger, Diplomacy, Simon and Schuster, New York, p. 374). That criticism is problematic. No international treaty can be enforced if there is no willingness to enforce it. True, the Kellogg-Briand Pact did not indicate what might occur should any of the signatories violate its terms. No enforcement mechanism was included in it. However, even if a clause had been added indicating what might happen, and/or mentioning an enforcement mechanism, in case of violation, that would not have helped unless those responsible for implementing such a clause would have been willing to do so when the moment arose. The main problem in international relations is usually not the lack of means, but rather the lack of willingness, to enforce an agreement.

No enforcement mechanism would have worked to prevent Nazi Germany, Fascist Italy, and Imperial Japan, which were bound by the Kellogg Brind Pact, from launching unprovoked military attacks, which clearly contravened its provisions. The League of Nations Covenant, which contained in it a call for collective action against an aggressor, did not deter any of the three aforementioned countries. Adding a clause to the Kellogg-Briand Pact aimed at deterring a potential violator of its provisions by threatening explicitly with concrete action might not have been enough to prevent them from carrying out their intended military attacks.

The principal problem entailed in the Kellogg-Briand Pact was not the fact that there was no explicit threat included in it in case its terms were to be violated nor, for that matter, that it lacked an enforcement mechanism.

It might be argued that the Kellogg-Briand Pact was founded upon a supposedly naïve belief about human nature and the way international relations are conducted.

Were the architects of the Pact unaware of the frailties of human behaviour and the anarchic nature of the international system?

Kellogg did not seem to entertain any idealistic notion about the Pact and its immediate success. In his speech in Oslo, upon being awarded the Nobel Peace Prize, on 10 December 1929, Kellogg said that “It is not to be expected that human nature will change in a day; perhaps it is too much to expect that the age-old institution of war, which has, through the centuries, been recognized by international law as a sovereign right […] will be at once abolished.”

He went on to argue that peace “can only be accomplished by slowly building the bulwarks of peace as peoples and nations have slowly and laboriously built the foundations of individual liberty and representative government.”

Kellogg stressed his message: “We must remember that it is difficult to abolish the century-old practices of nations in a day or in a year. Time must elapse to soften the animosities and deaden the fears of people”.

Final remarks

The Kellogg-Briand Pact should be assessed in its historical context. It was formulated a decade, more or less, after the end of World War I and a decade, more or less, prior to the outbreak of World War II. It came in the wake of the Locarno Treaty of 1925, which re-integrated Germany into the international scene as a leading diplomatic actor. The Kellogg-Briand Pact emerged in the midst of the so-called “Locarno Spirit” of reconciliation, which prevailed then in Europe.

For all its shortcomings, the Kellogg-Briand Pact ought to be seen for what it was, and for what it turned out to be: a watershed in international relations for the way it influenced the development of public international law and of diplomatic discourse. No legal analysis on the use of force in international relations can omit the Kellogg-Briand Pact as a landmark event. As Professor Malcolm Shaw wrote in International Law, ‘resort to force is not acceptable in international law, especially since the 1928 Kellogg-Briand Pact and article 2 (4) of the United Nations Charter.”

The Author

Yoav J. Tenembaum is a lecturer at the Diplomacy Studies Program, Tel Aviv University. He obtained his doctorate in Modern History from Oxford University and his Master’s degree in International Relations from Cambridge University. He read for his B.A. in History at Tel Aviv University.

His articles have been published in journals, magazines and newspapers in various countries. He has taught courses and seminars on International Conflicts, International Crises, International Organizations and Institutions and The Shaping of Foreign Policy and Decision-Making.

This article which was first published by the Cambridge International Law Journal is based on his recently-published book, Turning Points in the History of International Relations, 1908-2008.

To purchase Dr. Tenembaum’s book, please click here