Unpacking Key Assumptions Underlying Legal Analyses of the 2023 Hamas-Israel War

| Written By:

The current round of violence between Hamas and Israel has already given rise to many expressions of legal opinion. In this essay, we map some key assumptions and unpack how they can significantly affect ongoing legal debates and deliberations.

Photo by Chaim Goldberg/Flash90

The current round of severe violence between Hamas and Israel, sparked by the Oct. 7 incursion into Israel by Hamas militants and the terrible atrocities committed by them, has already given rise to many expressions of legal opinion. The assumptions underlying those legal opinions, however, have not been well illuminated or discussed. In this essay, we map some of the key assumptions and unpack how they can significantly affect ongoing legal debates and deliberations.

The range of legal opinions expressed in the ongoing war includes those by academic commentators (see e.g., here, here, and here), intergovernmental organizations (see e.g., here and here), NGOs (see e.g., here and here), think tanks (see e.g., here), journalists (see e.g., here), State officials (see e.g., here and here), and the ICRC (see e.g., here). These opinions display great diversity in the legal analysis offered, especially concerning a number of measures taken by Israel in response to the Oct. 7 attack: the tightening of the siege on Gaza and the cutting of humanitarian supplies from Israel to Gaza, the call on Palestinian civilians to leave the northern part of Gaza, and the extensive destruction inflicted on the Gaza Strip through IDF air strikes and, more recently, ground operations. The variance in legal analysis also manifests itself in the divergent positions of States on the General Assembly Resolution adopted on Oct. 27 calling for an immediate ceasefire, as well as for the rescinding of the Israeli evacuation order and unhindered supply of basic provisions to civilians throughout the Gaza Strip.

Such divergence of legal opinion may stem partly from differences in interpreting open-ended legal standards in international humanitarian law (IHL), such as definitions of proportionality, effective advance warning, displacement demanded by security of the civilians or imperative military reasons, objects in direct support of military action and “objects which by their nature, location, purpose or use make an effective contribution to military action and whose total or partial destruction, capture or neutralization, in the circumstances ruling at the time, offers a definite military advantage” (i.e., what constitutes a “military objective”). The application of such standards to specific sets of facts is notoriously difficult, especially in the “fog of war,” whose thickness might be exacerbated by deliberate disinformation campaigns by actors on both sides and their supporters, and now also by Israel’s efforts to disrupt the Gaza telecommunication infrastructure. Furthermore, there is little doubt that differences in ideology, worldview, political sympathy, and sociological background also affect the legal analysis offered by legal commentators (cf. ICTY prosecution report on NATO bombings, para 50).

Still, some of the divergence of opinions stems in our view from another source: Different appreciation of background legal assumptions against which legal analysis is conducted. Such background assumptions are often critical for the legal analysis – both because they might control the entire direction of the legal analysis and its ensuing accuracy, and because without agreement on background assumptions (or agreement to disagree on them) there is minimal possibility of different experts engaging in a fruitful conversation on the legal situation and the lawful measures that could or should be taken under it. Conversations of this nature are useless if their participants fail to acknowledge their differences of opinion about underlying assumptions.


Many discussions concerning the legal obligations of Israel toward the Gaza Strip, as well as the General Assembly Resolution of Oct. 27, appear to assume or else to be predicated on the idea that the Gaza Strip remains occupied, notwithstanding Israel’s withdrawal from it in 2005 (see e.g., here). We do not plan to revisit this debate here (for a discussion of the issue by two Israeli scholars, see for example, here and here); suffice it to say that the question is highly controversial and that even proponents of the approach that Gaza is occupied tend to concede that it is an unorthodox position, and that only parts of the laws of occupation apply in this situation, on a functional basis (see e.g., the ICRC’s Ferraro, pp. 157-158). Furthermore, a serious legal engagement with this question today must consider whether developments on the ground since 2005 – including the proven ability of Hamas to deploy a massive military raid into Israel from within Gaza – have strengthened or weakened the “remote control occupation” approach that was developed after 2005 (arguably, such an approach is based on a factual assessment regarding the ability of the occupier force to “make its authority felt within reasonable time”; cf. US DoD Law of War  Manual, Rule

Assuming that Israel still occupies Gaza might have dramatic implications for the jus ad bellum (the law governing the right to resort to force) analysis of the current situation.  Under those rules, there is no need to justify the resort to military force against a threat emanating from inside occupied territory (cf. ICJ Wall Advisory Opinion, para. 139). More significantly, it also affects the analysis of Israel’s obligations to supply basic humanitarian provisions to the Gaza Strip. Admittedly, the Israeli Supreme Court held in 2008 that such a duty exists, even though it held that the Gaza Strip is no longer occupied. Still, that judgment was premised on the actual dependency of Gaza residents on Israeli utilities, created during the long Israeli occupation of the Gaza Strip (from 1967 to 2005), and on Israel’s position, at the time, that it is required to provide essential goods to the Gaza Strip in order to avoid a humanitarian crisis. It is less than clear to what extent these rationales hold 15 years later given the many changes on the ground, including efforts to develop infrastructure inside Gaza (e.g., water desalination plants) and the passage of nearly two decades from the 2005 withdrawal.

Since there are no known parallels outside situations of occupation for a demand by one party to an armed conflict that the other party supply it with humanitarian provisions (including dual use supplies such as fuel),  the question whether the Gaza Strip is occupied or not is critical to the legal analysis of Israel’s obligations to provide itself humanitarian relief and the scope of any such obligations (in contrast, the obligation to allow humanitarian consignments by third parties, which IHL requires, is not seriously contested). It is also relevant for the analysis of the scope of Israel’s duties of care in matters such as arranging the evacuation of civilians away from danger and affirmatively providing health care services.

War Aims

Another element which appears to be largely missing from much of the analysis of the legality of specific measures undertaken by Israel is an analysis of its war aims, and the derivative military action designated to realize them, including means and methods of warfare adopted. From Israel’s point of view, the Oct. 7 attack has shifted the goal of its military strategy toward Gaza (where it has been in an armed conflict against Hamas since 2007) from a policy of containment to a policy directed at completely destroying the military and governance capacity of Hamas. Arguably, the new evidence on the extent of the threat posed by Hamas to Israel and to its ability to protect its citizens and its sovereignty, render these new war aims proportionate under jus ad bellum.

The broad scope of the war aims also affects the jus ad bellum proportionality analysis of the overall amount of force used in order to implement the said war aims, affording Israel – to the extent that Israel is able to justify its aims as commensurate to the real threat posed to it by Hamas – a broader operational latitude than that featured in previous rounds of extensive violence in and around Gaza. If the war aim were to be limited, under tests of jus ad bellum necessity and proportionality, to something narrower (like destroying Hamas’ rocket launching capacity, but not its governance capacity), that will affect the Israeli defense forces’ operational latitude.

These war aims set by Israel (eliminating Hamas’ military and governance capacity and, in addition, releasing the hostages) also affect the jus in bello analysis of the situation – especially with regard to evaluation of the legality of specific military targets and means and methods of warfare. The combined effect of Israel’s ambitious war aims and Hamas’s military strategy of embedding its operations in the midst of a densely populated city, including in massive underground fortifications, pushes Israel toward specific military acts, including attacking Hamas militants at their homes, clearing civilians and civilian infrastructure out of the way for large numbers of IDF ground troops to approach Hamas military locations, and rendering Hamas tunnels unsuitable for military use. This military strategy appears to underlie Israel’s policy of targeting residential dwellings harboring Hamas operatives, tall buildings overlooking major accessways to Hamas strongholds, and physical structures situated on top of Hamas “terror tunnels” – all causing very extensive damage to Gaza city infrastructure and resulting in many civilian casualties.

The ambitious war aims – assuming they are permissible as necessary and proportionate from a jus ad bellum perspective – do not, of course, release Israel from its duty of constant care, including with regard to precautions in each and every attack, and from the need to evaluate the jus in bello necessity, distinction, and proportionality of any single attack it conducts. Still, the war aims and their application to conditions on the ground in Gaza might render it difficult to draw definite conclusions, for instance, about the indiscriminate nature of the attacks, simply by reason of observing their significant scope and extent and the high numbers of civilian casualties. This is because the more ambitious the military campaign is, the larger is the potential number of military and dual-use targets that could serve its purposes and offer a definite military advantage. Drawing conclusions about targeting decisions is further complicated by the legal debate surrounding the degree of transparency obligations imposed on belligerent parties in relation to publicly specifying their target selection reasons and criteria.

In addition, the aforementioned war aims affect the analysis of the legality of IDF “large scale” warnings issued to the civilian population in Gaza City, which have been described by some as potentially forced displacement measures. In order to substantiate a claim that Israel must not attempt to move Palestinian civilians away from an anticipated urban warfare zone, one has to consider as part of the analysis whether the war aims, which the choice of means and methods of warfare is designed to serve, are illegal in light of the scope and extent of the overall anticipated humanitarian harm, or whether such war aims could be likely realized somehow through alternative military action, which would be less risky or harmful for the civilian population than evacuation of the area. That said, it may be an important reminder that IHL contains many prohibitions on belligerents’ conduct regardless of either side’s war aims. Claiming that an operation is militarily necessary to achieve a war aim will be no justification for violating certain IHL rules.

Use of Terminology

Some of the legal analysis of the Hamas-Israel war also appears to be based on crude use of terminology that often mixes common language use of terms with their specific legal meaning. Hence, for example, the term “total siege” used by Israel’s Defence Minister on Oct. 9 seems to imply, if translated into “legalese,” an unlawful policy under IHL, since intentional starvation of the civilian population can never be considered a lawful method of warfare. In practice, however, it appears that the “total siege” statement manifested itself in a ban on the transfer of humanitarian provisions from Israel into the Gaza Strip (although this ban has somewhat loosened in recent days), but reportedly not in a sweeping ban on entry of relief consignments from the Egyptian Rafah crossing (though the reporting here is mixed). Furthermore, while the northern part of the Gaza Strip remains largely inaccessible to humanitarian relief and is effectively under a partial military siege, the IDF strongly encourages civilians to move southwards – in ways that appear to meet at least some international interpretations of the laws of siege that regard allowing civilians to leave as one method to comply with such laws (provided that the option of leaving is feasible). All of this does not mean that Israel’s policy vis-à-vis access to humanitarian relief and the placing of a siege is fully compatible with IHL; rather it simply means that the term “total siege” used by the Israeli Minister cannot be the beginning and end of the legal analysis.

In the same way, the term “collective punishment” that was mentioned by the U.N. Secretary General appears to relate to a series of measures taken by Israel that adversely affect in a serious manner the civilian population in Gaza, including the termination of direct supply of utilities from Israel, a demand that the civilian population evacuate the north part of the Gaza Strip, and the targeting of civilian objects (which may have a dual use or purpose). Whereas collective punishment is strictly prohibited under IHL, this term does not apply to lawful measures that impact the civilian population, such as legally permissible retorsions, measures justified for civilian protection or imperative military necessity, and the targeting of dual use or dual purpose objectives (which may be lawful if it meets proportionality requirements and if feasible precautions are taken), whose goal is not punitive in nature. Every armed conflict entails measures that adversely affect the civilian population, and the impact of such measures on the civilian population might be harsh, individually and collectively. Still, this does not render them prohibited collective punishments in the legal sense of the term. More is needed to satisfy the definition.

Finally, it has already been observed many times (see e.g., here) that the use of the term “proportionality” in popular media discussions about armed conflicts differs significantly from its meaning under either jus ad bellum or jus in bello. Most obviously, IHL proportionality does not compare the amount of casualties on both sides but rather balances humanitarian harm against military objectives, and jus ad bellum proportionality examines the overall force used compared to its lawful aims (e.g., reversal of an ongoing attack or prevention of a recurrent attack).

At the same time, it would be a significant departure from IHL to suggest that proportionality analysis should weigh the overall military campaign benefits on the military advantage side of the equation; rather belligerents must apply the standard balancing of civilian harm and the concrete and direct military advantage from a target destroyed in a strike. One important nuance, however, is that the military advantage of each separate target could be considered in light of its contribution to the overall military campaign. Here too, more ambitious war aims might affect the military advantage weight assigned to specific targets.

Concluding Remarks

The upshot of this article is not to establish that the Israeli response to the brutal Oct. 7 attack by Hamas is lawful or unlawful under international law – this remains to be assessed from a variety of perspectives. And the more information on targeting decisions, means, and methods deployed, and anticipated humanitarian harm becomes available, the more informed such an assessment will be. Our claim is rather that an evaluation of the IDF response depends also on the evaluation of background legal assumptions, and that ignoring these dimensions of the analysis would render such an evaluation vulnerable to legal criticism and ultimately unpersuasive. In the same vein, the use by politicians and media commentators of terms that also have specific legal meaning does not relieve international lawyers from examining such terms’ actual manner of application to the complex, dynamic, and tragic situation in the Gaza Strip and Israel.


This article was published in JustSecurity.