The Use of Force [1]
The term “law of war” refers to both the
rules governing the resort to force (ius ad bellum) and the rules
governing the actual conduct of force (ius in bello) in International
Law.[2] 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.[3] 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.[4]
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
injustum) arose as a consequence of the Christianization of the Roman Empire and the abandonment by Christians of
pacifism.[5] 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
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).[8] 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
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 .[13]
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.[14] 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.[15]
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).[16] 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.[17] 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.[18] 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.[19] 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.[20]
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.[21] 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).[22] 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.”[23]
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.[24] A fourth exception is formulated by the 1974
General Assembly Resolution on “the Definition of Aggression”[25]
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.[26]
(1) The Right of Self-Defense [27]
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
pre-emptive) 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.[28] 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 pre-emptive)
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).[29] 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.[30] 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.[31] 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.[32] 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.[33]
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”.[34] 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.[35]
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
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.
[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
[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.
[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
[29] See
e.g. J. L. Brierly, The Law of Nations, pp. 417-8, 6th
ed., Oxford
[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.
