International Humanitarian Law Commons^™

Revisiting Ad Bellum Proportionality: Challenging The Factors Used To Assess It, Yishai Beer

International Law Studies

Traditionally, international law has established a binary distinction between jus ad bellum and jus in bello. The former relates to the right to exercise military force. The latter regulates the conduct of adversaries engaged in an armed conflict. However, the prevailing legal approach doesn't accept this dichotomy. It wants to reduce war's hazards by applying the ad bellum rules, including the proportionality requirement, continuously throughout the conduct of armed conflict. To that end, it has established factors that define the essence of the continuing ad bellum proportionality requirement. This article challenges the near-unanimous consensus regarding these factors. It argues that …

The Plea Of Necessity: An Oft Overlooked Response Option To Hostile Cyber Operations, Louise Arimatsu, Michael N. Schmitt

International Law Studies

States are increasingly focused on the measures—cyber or otherwise—that they can take in response to hostile cyber operations. Although cyber operations are usually responded to with acts of “retorsion” (acts that are lawful, although unfriendly), international law recognizes other self-help mechanisms that allow for more robust responses. In the cyber context, most attention has focused on countermeasures and self-defense. Yet, both are subject to various limitations that constrain their availability.

This article examines a further option, the so-called “plea of necessity.” It allows States to respond to a hostile cyber operation when the action taken would otherwise be unlawful but …

Application Of The Due Diligence Principle To Cyber Operations, Tomohiro Mikanagi

International Law Studies

The discreet use of proxies by States renders it difficult to prove attribution to States under the existing rules of attribution. On the other hand, the due diligence principle, if applicable, does not require attribution but can lead to the invocation of State responsibility for cyber operations emanating from the territory of other States. In the Corfu Channel judgment the ICJ recognized “every State’s obligation not to allow knowingly its territory to be used for acts contrary to the rights of other States,” and UN Member States agreed that existing international law applies to cyber operations. However, the UN Members …

Legal Advisers In The Field During Armed Conflict, Yoram Dinstein

International Law Studies

Additional Protocol I to the Geneva Conventions of 1949 requires that legal advisers be made available to military commanders, particularly during hostilities. This treaty stipulation was quite innovative in 1977, but it has achieved widespread implementation, even among non-Contracting Parties. It is noteworthy that the United States—which objects to numerous provisions of Additional Protocol I—does not dissent from the article requiring legal advisers. A study of the practice of States, made by the International Committee of the Red Cross, confirms that the norm requiring that legal advisers be made available to advise military commanders in time of armed conflict currently …

Military Action To Recover Occupied Land: Lawful Self-Defense Or Prohibited Use Of Force? The 2020 Nagorno-Karabakh Conflict Revisited, Tom Ruys, Felipe Rodriguez Silvestre

International Law Studies

In September 2020, heavy fighting erupted between Armenia and Azerbaijan in and around Nagorno-Karabakh, a region of Azerbaijan long controlled by Armenia. After two months of military confrontations, a tripartite ceasefire was concluded, drastically altering the pre-existing territorial status quo.

The "Second Nagorno-Karabakh War" brings to light a fundamental question for international law on the use of force—and one that has received limited attention in legal doctrine. The question is this: when part of a State’s territory is occupied by another State for an extended period of time, can the former still invoke the right of self-defense to justify …

Developing International Guidelines For Protecting Schools And Universities From Military Use During Armed Conflict, Steven Haines

International Law Studies

One consequence of armed conflict, especially that of a non-international character, is serious damage done to vital societal infrastructure. Education–schools and universities–can be severely disrupted, even subject to attack. Targeting of schools may not invariably be unlawful if educational facilities are being put to military use. Such use may itself not be unlawful but it can result in schools being transformed from civilian objects into military objectives–and subject, therefore, to lawful targeting. This was a problem highlighted by humanitarian NGOs a decade ago and led to the formation, by both NGOs and United Nations agencies, of the Global Coalition to …

Command Accountability For Ai Weapon Systems In The Law Of Armed Conflict, James Kraska

International Law Studies

The use of artificial intelligence (AI) in weapon systems enhances the ability of operational forces to fuse multispectral sensors to understand the warfighting environment, positively identify, track, and select targets, and engage them with the most appropriate effects. The potential for AI to help close the “kill chain” has raised concern that this creates a gap in accountability between the decisions of humans and the acts of machines, with humans no longer accountable for decisions made during armed conflict. This study suggests that there is no gap because the military commander is always directly and individually accountable for the employment …

Armed Conflicts In Outer Space: Which Law Applies?, Frans G. Von Der Dunk

International Law Studies

So far, outer space has merely become involved in terrestrial armed conflicts as part of the supportive infrastructure for military activities. Unfortunately, the risk that this changes is considerably growing, and it can no longer be excluded that (armed) force will become used in outer space, either directed towards Earth or within outer space itself.

This raises serious issues in the legal context, where space law so far has been premised on the hope that armed conflicts in outer space could be avoided whereas the law of armed conflict was not required so far to deal with the use of …

Responding To Hostile Cyber Operations: The “In-Kind” Option, Michael N. Schmitt, Durward E. Johnson

International Law Studies

Facing hostile cyber operations, States are crafting responsive strategies, tactics and rules of engagement. One of the major challenges in doing so is that key aspects of the international law governing cyber responses are vague, unsettled or complex. Not surprisingly, therefore, international law is markedly absent from strategies and operational concepts. Rather, they tend to take on a practical “tit-for-tat” feel as policymakers logically view “in-kind” responses as “fair play.” For them, responding in-kind surely must be lawful notwithstanding any challenges in discerning the precise legal character of the initial hostile cyber operation.

Testing that sense, this article examines the …