By Matthijs de Blois.
The brutal surprise attack on Israel and its citizens by Hamas and other Islamist militants shocked at least part of the world. The cruelty of the violence against innocent civilians, including babies, children and elderly people is almost beyond comprehension.
Many agree that Israel has under international law the inherent right to defend itself, as is confirmed by Article 51 of the UN-Charter. Israel has the right to bring about a definitive end to the capacity of the terrorists to kill, maim and kidnap all those citizens and foreigners on its territory. The suggestion by the International Court of Justice in the Wall Advisory Opinion of 2004, that the right to self-defense can only be invoked against aggression by a State has no foundation whatsoever in international law. Israel was attacked by Hamas terrorists operating from the Gaza Strip into Israel. These hostile forces did not respect international humanitairan law (IHL) in any way. They started the conflict by violating all its basic principles by killing, maiming, torturing, raping and kidnapping innocent civilians of all ages.
Hamas also has already a long tradition of targeting civilian persons and objects in Israel. But notwithstanding, Israel is bound by IHL, as was made clear by those who recognized Israel’s right to self-defense. This recognition of this right has in general been qualified by the requirement that the Jewish State should respond “with restraint” or “proportionately”. For example, the Secretary General of NATO said after a meeting of the defense ministers of the Member States on 11 October 2023:
“Allies expressed solidarity with Israel, making clear that it has the right to defend itself with proportionality against these unjustifiable acts of terror.”
This cautious approach seems to be at odds with what had been concluded on the same day by the Head of State of one of the NATO Member States, Turkish President Erdogan that the response of Israel was a disproportionate and amounting to a ‘massacre’.
The issue here is the application by Israel of one of the most important principles of international humanitarian Law: proportionality. It is a criterion to determine whether the exercise of military power of a State to defend itself is justified.
The principle of proportionality is part of international customary law and is articulated in Article 51(5)(b) of Additional Protocol I of the Geneva Convention, which prohibits the use of indiscriminate attacks and the use of disproportionate violence. It prohibits:
|“an attack which may be expected to cause incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof, which would be excessive in relation to the concrete and direct military advantage anticipated.”|
This provision implies that, before undertaking an attack, which may cause harm to civilians or civilian objects, serious consideration of these interests as well as of the military objectives should take place, to prevent a disproportionate action. It is implicit in the provision that the fact that civilians and civilian objects are hit by military action does not automatically mean that the military action is disproportionate.
Proportionality applies tomilitary operations against combatants. However, as is clear from the provision quoted, it also applies to non-combatants; in other words, the collateral damage caused by the military action must be proportional to the military advantage the action is intended to achieve.
Proportionality in the context of the war going on now in Israel and the Gaza strip is about balancing the protection of innocent civilians and the military objective. As specified by Robert Kolb:
“The point is not that a belligerent must ensure a certain balance (positive proportionality), but that it must avoid a manifest imbalance (negative proportionality, excess).”
Proportionality refers to an assessment not only of the military objective but also of the results that may be reasonable expected of the action that will be taken. The law does not require of the soldiers involved a superhuman ability to foresee the future. It is about reasonable expectations. And the consideration of the proportionality must be made during times of war, which generally offer little opportunity for reflective consideration. It is a consideration made by those responsible in the field that only sometimes subsequently will be reviewed by a court.
Moreover the assessment of proportionality is not a mathematical exercise – contrary to what is frequently the idea of the press and the general public. Proportionality requires no equality of the number of casualties on both sides. What is relevant is not the final outcome of the battle but the initial decision to prevent a manifest imbalance between the military objective and the expected losses among the civilians. As formulated by Kolb:
“the rule we are discussing [proportionality] shows how wrong the usual reflex of the journalists is, when they conclude from the death of a number of civilian persons that there is a violation of IHL.”
The application of the principle of proportionality in the case of the military action by Israel against the Hamas terrorists in Gaza is complicated by the fact that it is part of the tactics or even the strategy of Hamas to use civilians as human shields. Military operations are conducted from civilian locations, such as private homes, schools, hospitals, and mosques. Furthermore, Hamas is structured in such a way that it is difficult to make a clear distinction between public services provided by “military” organizations and public services provided by “civic” organizations. The use of civilians and civilian objects as human shields fits what Kittrie calls compliance-leverage disparity lawfare.
This last variety refers to the use that is made by an actor “to gain advantage from the greater leverage that international law and its processes exert over an adversary.” This is typically something which is at stake in cases of asymmetric warfare. It is profiting by an actor (for example terrorist groups like Hamas or the Islamic Jihad) from the fact that the adversary (for example Israel) will be more inclined to respect international law and therefore more limited in the way it will response to the action of the first actor. To fight from civilian objects and hide behind civilians, either prevents a State to respond, or, in case of a response with casualties, to cause an avalanche of public and official condemnations of the State as violator of international (humanitarian) law. The condemnations of the terrorist organization, if any, will be much more limited.
Is has to be underlined that notwithstanding the Hamas practice is a serious violation of IHL, Article 28 of the Fourth Geneva Convention stipulates that the presence of a person protected by humanitarian law may not be used to render certain points or areas immune from military operations. Moreover, the ultimate responsibility for the death or injury of civilians who are used as a shield for military activities lies with the party that used the civilians for this purpose. Article 51(7) of Additional Protocol I states:
“The presence or movements of the civilian population or individual civilians shall not be used to render certain points or areas immune from military operations, in particular in attempts to shield military objectives from attacks or to shield, favour or impede military operations. The Parties to the conflict shall not direct the movement of the civilian population or individual civilians in order to attempt to shield military objectives from attacks or to shield military operations.”
The practice of Hamas discussed will inevitably have an effect on the assessment of the proportionality of the Israeli response to the atrocities of the terrorists. Israeli military commanders are allowed to take into account the use of civilians for which Hamas or its affiliates, and not the IDF, are responsible. That means that if the expected number of casualties is higher than would be the case when Hamas did not use civilians or civilians objects as ‘human shield’, the military action undertaken would arguably remain within the limits of the requirement of proportionality. It is against IHL to reward the use of human shields.
 Article 51(5)(b) of Additional Protocol I of the Geneva Convention.
 Idem, p. 172.
 Robert Kolb, Advanced Introduction to International Humanitarian Law, Edward Elgar, Cheltenham, UK, Northampton, MA, USA, 2014, p. 173.
 Orde F. Kittrie, Law as a Weapon of War. Lawfare, Oxford University Press, 2016, pp. 17-28, 284-295.
 Ibidem , p.17.