The Use of Force


The term “law of war” refers to both the rules governing the resort to force (jus ad bellum) and the rules governing the actual conduct of force (jus in bello) in International Law. Because each of these two types of rules governs different subject matters, it is reasonable to deal with them separately. Therefore, this chapter is devoted to deal with the rules governing the resort to force; while the next chapter entitled “International Humanitarian Law” is devoted to deal with the rules governing the actual conduct of force.
The rules governing the resort to force form a central element within International Law. These rules together with other principles such as territorial sovereignty, independence and equality of States provide the framework for the international order. While a domestic system prescribes the monopoly on the use of force by a State, through its governmental institutions, in order to enable the State to preserve its authority and maintain its control within its territory, the International Law seeks to minimize and regulate the use of force by States in their international relations in order to preserve and maintain peace and security in the world community.
The position of International Law towards the use of force by States has not been the same throughout the history. Because of this fact, in the following sections we will deal with the use of force, first, before 1945, the establishment of the United Nations, and second, under the Charter of the United Nations.

Section 1: The Rules Related to the Use of Force Before 1945
“War” is the apparent manifestation of the use of force by States. It is a status or condition of armed hostility between States. It comes into existence either by a formal declaration or by acts of armed force between States without a formal declaration.
Early in History, war was resorted to for various reasons and causes without any distinction, and was conducted without any limitation and control. The distinction between “just war” (bellum justum) and “unjust war” (bellum justum) arose as a consequence of the Christianization of the Roman Empire and the abandonment by Christians of pacifism. The doctrine of “just war” was founded on the belief that force could be used if it complied with the divine will. Just war was to be employed as the ultimate sanction for the maintenance of an orderly society. St Augustine (354-430) defined the just war in terms of avenging of injuries suffered where the guilty party had refused to make reparation. War was to be employed to punish wrongs and restore the peaceful status quo, nothing further. Aggression was unjust. The resort to force should be strictly controlled. St Thomas Aquinas in the Thirteenth Century went a further step in the definition of just war by declaring that war could be justified provided it was waged by sovereign authority, it was accompanied by just cause, i.e. the punishment of wrongdoers, and it was supported by the right intentions on the part of the belligerents.
The teachings of the Christian theologians on distinguishing between just war and unjust war were eventually adopted by the early classical writers on “the law of nations”, such as Alberico Gentili (1552-1608) and his successor Hugo Grotius (1583-1645). However, all of these writers took a different approach on this question in the light of the rise of the European nation-states and eventually modified the doctrine of just war. The doctrine became linked with the sovereignty of States, and it was approached in the light of wars between Christian States, each side being convinced of the justice of its cause. The early writers on the law of nations approached the doctrine of just war from a purely subjective point of view, admitting the possibility of both sides having a just cause and believing in being in the right even though one of them might have been objectively wrong. Thus, the doctrine of just war could not be objectively applied to determine whether or not a war was just, and consequently the distinction between just war and unjust war never became part of the law of nations. Eventually, in the Eighteenth Century, the distinction was virtually abandoned by the law of nations.
The doctrine of the just war that arose with the increasing power of Christianity declined with the outbreak of the inter-Christian religious wars and the establishment of an order of secular national sovereign States in Europe.
In the Nineteenth Century, war in the practice of the European States was often represented as a last resort, as a means of dispute settlement. The resort to war was regarded as an attribute of statehood. War was a legal state of affairs in International Law. It was to be justified if it was fought for the defense of certain vital interests. Each State remained the sole judge of its vital interests. Vital interests constituted a source for political justifications and excuses used for propaganda purposes, not a legal criterion of the legality of war. There also existed other methods of employing force that fell short of war, such as reprisals and blockades.
The international jurists of the Nineteenth Century abandoned emphases on the legality of war (jus ad bellum), and concentrated on the legality of the conducts of war (jus in bello). Therefore during this century, a series of regulatory conditions and limitations on the conducts of war, or of force in general, were recognized under International Law in order to minimize the resort to war, or at least to restrict its application. There also existed legal consequences resulting from the exercise of the right to resort to war.
The unprecedented suffering of the First World War caused a revolutionary change in the attitudes towards war. The doctrine of just war was revived after this war. The creation of the League of Nations in 1919 constituted an effort by the world community to rebuild international affairs upon the basis of a general international institution which would oversee the conducts of the States to ensure that aggression could not happen again. The Covenant of the League of Nations, although it did not prohibit the resort to war altogether, it introduced a different attitude, than that existed previously, to the question of war in International Law. The Covenant set up procedures designated to restrict the resort to war to tolerable levels. It declared that members of the League agreed that they would submit their disputes, which likely to lead to a rupture, either to arbitration or judicial settlement, or to inquiry by the Council of the League. The members also agreed that in no case they would resort to war until the elapse of three months after the award by the arbitrators or the judicial decisions, or the report by the Council.
During the years following the creation of the League of Nations, various efforts were made to fill the gap in the League system, which is to transform the partial prohibition of war into total prohibition of war. These efforts resulted in the conclusion of the General Treaty for the Renunciation of War in 1928 (known as the Kellogg-Briand Pact or Pact of Paris). The parties to this multilateral treaty condemned recourse to war for the solution of international controversies, agreed to renounce war as an instrument of national policy in their relation with one another, and agreed to settle all disputes or conflicts only by pacific means. This trend was adopted by the Charter of the United Nations in 1945.

Section 2: The Use of Force under the Charter of the United Nations
The Charter of the United Nations establishes a fundamental distinction between legal and illegal resort to force. By this, it has, in a way, revived in International Law the old distinction between just and unjust war. Moreover, it goes further than the position of the classical international law towards the use of force. While the classical international law did not place any restriction on the right of States to use force and to go to war, the Charter of the United Nations provides provisions aiming to control the use of force, on one hand prohibiting the use of force, and on the other hand permitting the use of force in exceptional cases.

A. The Prohibition of the Use of Force
The preamble of the Charter of the United Nations starts with the determination of the peoples of the United Nations to save succeeding generations from the scourge of war, and their willingness to practice tolerance and live together in peace with one another as good neighbors, and not to use armed force except in the common interest. To this end Article 2(4) of the Charter provides:
All members shall refrain in their international relations 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.
This article formulates the principle of the prohibition of the use of force in International Law, by imposing upon the States members of the United Nations the basic obligation to refrain from the threat or use of force in their international relations. The provision of this article, which marks the general acceptance of the prohibition of the use of force in international relations, is of universal validity. The principle of prohibition of the use of force bounds the States members of the United Nations and the United Nations itself, as well as, the few States which are not members of this international organization since it is a principle of customary international law. Article 2(4) mentions the use of force not the resort to war; by this, it intends to include in the prohibition all sorts of hostilities, short of war, in which States may be engaged. It prohibits not only the use of force but also the threat of force.
The prohibition of the threat or use of force in international relations against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations, as stated in Article 2(4), is reinforced by other provisions of the Charter, particularly paragraph 3 of the same article. Article 2(3) imposes upon States the obligation to “settle their international disputes by peaceful means in such a manner that international peace and security, and justice, are not endangered.” Furthermore, this prohibition is elaborated as a principle of International Law in the 1970 General Assembly “Declaration on Principles of International Law Concerning Friendly relations and Co-Operation among States in According with the Charter of the United Nations.”
The 1970 Declaration on Principles of International Law provides that the threat or use of force constitutes a violation of International Law and the Charter of the United Nations and should not be employed as a means of settling international issues. It declares that a war of aggression constitutes a crime against peace, for which there is responsibility under International Law. It lists systematically the obligations of States in this regard. Every State has to refrain from propaganda for wars of aggression. It has to refrain from the threat or use of force to violate the existing international boundaries of another State, or the international lines of demarcation. It has to refrain from acts of reprisal involving the use of force. It has to refrain from any forcible action which deprives peoples of their right to self-determination, freedom and independence. It has to refrain from organizing, instigating, assisting or participating in acts of civil strife or terrorist acts in another state, or acquiescing in organized activities within its territory directed towards the commission of such acts.
The Declaration provides that the territory of a State shall not be the object of military occupation or acquisition by another State resulting from the threat or use of force, and that such territorial acquisition shall not be recognized as legal.
The Declaration obliges all States to comply in good faith with their obligations under the generally recognized principles and rules of International Law with respect to the maintenance of international peace and security, and to make the United Nations security system based upon the Charter more effective.
The Declaration, however, provides that its provisions shall not construed as enlarging or diminishing in any way the scope of the provisions of the Charter concerning cases in which the use of force is lawful. By this provision, the Declaration reaffirms the exceptions to the principle of the prohibition provided for in the Charter of the United Nations.

B. The Exceptions to the Prohibition of the Use of Force
The Charter of the United Nations formulates two exceptions to the principle of the prohibition of the use of force in international relations. The first exception is the use of force in a case of exercising the right of individual or collective self-defense under Article 51. The second exception is the use of force by authorization of the Security Council of the United Nations under Chapter VII.
The 1950 General Assembly “Uniting for Peace” Resolution formulates a third exception to the principle of the prohibition of the use of force, which is the use of force upon a recommendation of the General Assembly. A fourth exception is formulated by the 1974 General Assembly Resolution on “the Definition of Aggression” which entitles the people forcibly deprived of the right to self-determination, or under colonial domination or alien subjugation, to struggle to achieve their objectives in self determination and independence.

(1) The Right of Self-Defense
Article 51 of the Charter of the United Nations provides:
Nothing in the present Charter shall impair the inherent right of individual
or collective self-defense if an armed attack occurs against a Member of the
United Nations, until the Security Council has taken the measures necessary
to maintain international peace and security. Measures taken by Members in
the exercise of this right of self-defense shall be immediately reported to the
Security Council and shall not in any way affect the authority and
responsibility of the Security Council under the present Charter to take at any
time such action as it deems necessary in order to maintain or restore
international peace and security.
This article formulates the major exception to the prohibition of the use of force in international relations. It indicates that the right of individual and collective self-defense, which existed under customary international law, is reserved to the extent it is qualified therein and elsewhere in the Charter of the United Nations.
The right of self-defense, as formulated by the Charter, is a subject of an extensive controversy as regards its precise extent. Does Article 51 clarify or qualify the right of self-defense which exists in the customary international law? Is the anticipatory (preventive or preemptive) self-defense included within the meaning of the right of self-defense formulated in Article 51? What is the meaning of the term “armed attack”?
There are two conflicting interpretations of the right of self-defense formulated in Article 51 of the Charter of the United Nations, namely the restrictive view and the broad (extensive) view. The restrictive view indicates that all use of force is illegal except in the exercise of the right of self-defense if and only if an armed attack occurs. This means that the right of self-defense does not exist against an action which does not constitute an armed attack, whatever the nature and extent of such action. Moreover, this implies that anticipatory (preventive or preemptive) self-defense is not permitted under Article 51 of the Charter of the United Nations. The argument for this view is that the principle of effectiveness requires a restrictive interpretation of Article 51. Such interpretation is consistent with Article 2(4) of the Charter which intends only to clarify the prohibition on the use of force and not to qualify it. It is also consistent with the view that Article 51 is intended to modify the right of self-defense which has existed in customary international law; Article 51 qualifies the existing right of self-defense.
The broad (extensive) view indicates that the use of force in self-defense is excluded from the scope of Article 2(4). The right of self-defense, which has existed as an inherent and natural right in customary international law, is over and above the specific provisions of Article 51 which refer only to the case where an armed attack has occurred. The right of self-defense is allowed against an armed attack as well as against any other hostile action short of an armed attack. This implies that anticipatory self-defense comes within the meaning of Article 51, which does not intend to impair the scope of the inherent right of self-defense existing in customary international law. Accordingly, the protection of nationals abroad, the protection of property situated abroad, an attack against an individual-national abroad, the war against terrorism, or the existence of weapon of mass destruction in a given State, may justify the exercise of the right of self-defense.
Whatever the view concerning the right of self-defense, it is well recognized that for the exercise of this right customary international law requires three basic legal requirements: the use of peaceful procedures--if they are available, necessity and proportionality. These three requirements represent three central elements which must be complied with under customary international law in order to invoke self-defense lawfully against illegally initiated force.
Self-defense is justified only when the necessity for action is instant, overwhelming, and leaves no choice of means and no moment for deliberation. Acts done in self-defense must not be unreasonable or excessive, since the acts justified by a necessity of self-defense must be limited to that necessity and
kept within it. Proportionality in coercion requires that the responding coercion be limited in intensity and magnitude to what is reasonably necessary promptly to secure the permissible objectives of self-defense.
Article 51 of the Charter seems to demand a higher degree of necessity than the customary international law. Under this article, the right of self-defense does not exist against any form of action which does not constitute “armed attack”. Self-defense is justified against an actual danger, something that has taken place, not against a threat of use of force. Nothing less than “armed attack” shall constitute a justifying act for the exercise of the right of self-defense. So “preventive war” is prohibited under this article.
Article 51 adds a forth requirement to the three requirements of customary international law for justifying the exercise of self-defense. It requires the Member State to report immediately the measures taken in the exercise of the right of self-defense to the Security Council, and to stop its action when the Security Council takes the necessary measures in this regard.
In conclusion, the Charter recognizes the right of member States, acting individually or collectively, to declare war against an aggressor and to take military action against him until the Security Council takes the measures necessary to maintain international peace and security.
(2) The Use of Force by Authorization of the Security Council
The second exception to the prohibition of the use of force in international relations is formulated in Article 42 of Chapter VII of the Charter of the United Nations. Article 42 provides that the Security Council may take such coercive military action by air, sea, or land forces as may be necessary to maintain or restore international peace and security. Such action may include demonstrations, blockades, and other operations by air, sea, or land forces of Members of the United Nations. This means that the Security Council has the power to order or authorize the use of force or, in traditional terminology, the resort to war. However, the Council is required to fellow the procedures provided for in Chapter VII of the Charter of the United Nations.
(3) The Use of Force upon a Recommendation of the General Assembly
The “Uniting for Peace” Resolution, adopted by the General Assembly on November 3, 1950, grants the General Assembly of the United Nations the power to act in place of the Security Council if the latter fails to discharge its primary responsibility in maintaining international peace and security. Under this resolution, the General Assembly may do by recommendations anything that the Security Council can do by decisions under Chapter VII. The Assembly can make appropriate recommendations to members for collective measures, including the use of armed force, if the Council in any case where there appears to be a threat to the peace, breach of the peace or act of aggression fails to exercise its responsibility, because of the lack of unanimity of its permanent members.
(4) The Use of Force by Peoples for Self Determination and Independence
Article 7 of the 1974 General Assembly Resolution on “the Definition of Aggression” grants the peoples forcibly deprived of their right of self-determination, freedom and independence, particularly
peoples under colonial and racist regime or other forms of alien domination, the right to struggle for the purpose of achieving their self determination, freedom and independence. This implies that those peoples can use armed force in their struggle, and this is a forth exception to the principle of prohibition of the use of force in international relations.


References:
[1] See generally Brownlie, chapter 33; Y. Dinstein, War, Aggression and Self-Defence, 3rd ed., Cambridge (2001); T.M. Franck, Recourse to Force, Cambridge (2002); C. Gray, International Law and the Use of Force, Oxford (2001); Malanczuk, chapter 19; and Shaw, chapter 20.
[2] See Malanczuk, p. 306.
[3] Shaw, p. 1013.
[4] Id.
[5] Shaw, pp. 1013-4.
[6] Id. p. 1014.
[7] See S. Bailey, Prohibitions and Restraints in War, p. 9, Oxford (1972); and Von Elbe, The Evolution of the Concept of the Just War in International Law, 33 A.J.I.L. 669 (1939).
[8] See Bledsoe & Boczek, p. 336; also Malanczuk, pp. 306-7; and Shaw, pp. 1014-5.
[9] Shaw. p. 1014.
[10] Bledsoe & Boczek, p. 336.
[11] Id.
[12] Id.; and Malanczuk, p. 307.
[13] Shaw, p. 1016.
[14] Brownlie, p. 697.
[15] See Shaw, p. 1016.
[16] Bledsoe & Boczek, p. 336.
[17] Formulated in The Hague Conventions of 1899.
[18] Malanczuk, p. 308
[19] L.N Covenant art. 12(1).
[20] Id.
[21] See Malanczuk, p. 308-9; and Shaw, p. 1017.
[22] Text in 94 L.N.T.S. 57 (1929).
[23] G.A. Res. 2625 (XX!), 25 GAOR, Supp. 28, U.N. Doc. A/8028, at 121 (1970). [hereinafter cited as the “Declaration on the Principles of International Law”]
[24] G.A. Res. 337(a) (V), 5 GAOR Supp. 20, U.N. Doc. A/1775, at 10 (1950).
[25] G.A. Res. 3314 (XXIX), 29 GAOR Supp. 31, U.N. Doc. A/9631, at 142 (1974).
[26] Id. art. 7.
[27] See generally D.W. Bowett, Self-Defence in International Law, Manchester (1958); Brownlie, pp. 701-3; Dinstein, chapters 7 and 8; Franck, chapters 3-7; Gray, chapter 4; Malanczuk, pp. 311-18; and Shaw, pp. 1024-32;
[28] See e.g. H. Kelsen, The Law of the United Nations, pp. 914, London (1950); and J.L. Kunz, The Changing Law of Nations, pp. 563-74 (1968);
[29] See e.g. J. L. Brierly, The Law of Nations, pp. 417-8, 6th ed., Oxford (1963); McDougal & Feliciano, pp. 217-44; and D.P. O’Connell, International Law, p. 317, 2nded., London (1970).
[30] See C.C. Hyde, I International Law, pp. 237-40 & 821-22, 2nd ed., Boston (1945).
[31] Id.
[32] Id.
[33] See McDougal & Feliciano, at 242.
[34] See Kunz, at 571; and Kelsen, at 269.
[35] Kunz, id.; and Kelsen, id.