The methods adopted by the League for the prevention of war have proved up to now so effective as to encourage further hope in the future. It has so far been responsible for the peaceful settlements of disputes, such as that between Sweden and Finland over the Aaland Islands, between Germany and Poland upon the Upper Silesian frontier, between Serbia and Greece and Albania in respect of the latter's boundaries, between Poland and Czecho slovakia upon a similar boundary dispute, between Great Britain and Turkey in regard to the frontiers of 'Iraq, in the Memel incident in January 1923 and in the very grave dispute between Greece and Bulgaria in October 1925. Any one of these incidents might have led to war but for the timely intervention of the League.
The Locarno Pact strove to complete the League of Nation's organisation by definitely securing the adhesion of Germany and eliminating thus that most critical dispute between France and Germany which had proved such a source of wars in Europe. By the Treaty of Mutual Guarantee concluded on October 16, 1925, Germany and France and also Germany and Belgium undertook "that they will in no case attack or invade each other or resort to war against each other." They undertook, further, to settle by peaceful means "all questions of every kind" which might arise between them and which could not be settled by diplomacy. This involves submission to the Permanent Court of International Justice or to a Court of Arbitration of all "questions as to their respective rights," viz., judicial disputes, and reference to a Per manent Conciliation Commission of "all other questions." Fail ing settlement by conciliation, the dispute is to be dealt with by the Council of the League of Nations. This compulsory sub mission to judicial settlement or arbitration accepted by France, Germany and Belgium applies also as between Germany and Poland and Germany and Czechoslovakia and constitutes a great step in advance of article 13 of the Covenant of the League which makes such submission voluntary and not compulsory.
The Paris Peace Pact, 1928.—Whilst the League of Nations is the most effective instrument of peace ever devised, it does not completely abolish war, as under articles 15 and 16 of the Covenant both a collective war and an individual war still remain possible either as an ultimate sanction of the League's resolu tions or in case all peaceful means have failed. To fill up this gap, a multilateral treaty, known as the Paris Peace Pact, was signed on August 27, 1928, for the "renunciation of war." By December 5, 1928, fifty-nine nations out of the sixty-four inde pendent States of the world, had adhered to the Pact. In July 5929 the U.S.A. declared the Pact in operation ; subsequently every sovereign State except three South American Republics agreed to it. The initiative for the conclusion of this treaty rests with Monsieur Briand, the French Foreign Secretary, and the United States Secretary of State, Mr. Kellogg, and followed closely on the Resolution passed unanimously in September 1927 by the Eighth Assembly of the League of Nations that "all wars of aggression are and shall always be prohibited" and that "every pacific means must be employed to settle disputes of every description which may arise between States." The Paris Pact extends this prohibition to all wars generally and not only to wars of "aggression" which are in fact incapable of any exact definition.
The Pact is a very brief document consisting of three articles only, the last of which is merely a formal one dealing with ratification. The important principle is contained in article I that "the High Contracting Parties solemnly declare, in the name of their respective peoples, that they condemn recourse to war for the solution of international controversies and renounce it as an instrument of national policy in their relations with one another." The article has been purposely drafted in such gen eral terms so as to include all international differences which may arise between the parties and covers therefore not only justiciable disputes, but also political and economical contro versies and, generally, all disputes other than domestic ones. On the other hand, the renunciation of war is expressly limited to wars undertaken as "an instrument of national policy"—a term which, according to the official interpretation placed upon it by Mr. Kellogg, excludes wars resorted to under the "inalienable right of self-defence" (United States Note of June 23, 1928, The Times, June 25, 1928). The expression itself of an "instrument of national policy" is not defined in the Pact, but the official note of the French Foreign Office of April 19, 1928, explains the words as meaning "an instrument of personal, spontaneous and inde pendent political action in which States take the initiative and not as an action in which they find themselves involved by the appli cation of a treaty such as the Covenant of the League or any other treaty registered at the League of Nations." It must therefore be presumed that the Pact does not prohibit wars under taken collectively as a measure of international sanction or co ercion, but only wars undertaken by an individual State or group of States in their own interest and not on behalf of the com munity of nations. Even with this limitation, the Pact assumes the character of the most important international event since the establishment of the League of Nations since it deprives of its legitimacy the right to go to war which has hitherto been regarded as an attribute of sovereignty of every independent State. Up to and including the World War, it has always been a common habit of diplomacy to attach to every proposal for the settle ment of a dispute the threat that failure to comply therewith would be followed by war. In the words of Clausewitz war is "an instrument of national policy whereby one nation imposes its will upon another." The Pact takes away this custom of associating warfare with national prestige or interest and com mits the contracting parties to the fundamental principle that war ought to be "delegalised" in the international sphere as it has already been delegalised inside every civilised State. It also creates a basis upon which the United States and Russia—not at present members of the League of Nations—can co-operate with the rest of the world in maintaining peace by the solemn declaration agreed to by all the signatory Powers that the "settle ment or solution of all disputes or conflicts, of whatever nature or of whatever origin they may be, which may arise between them, shall never be sought except by pacific means" (article 2 of the Pact).