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Military Ai And The Specter Of The Limitless War, Yuval Shany, Yahli Shereshevsky

International Law Studies

Legal and extra-legal factors related to the development of international humanitarian law (IHL) support the exercise of strategic restraint during armed conflicts. We claim, however, that technological developments in the area of military artificial intelligence (AI) fundamentally do away with many of the technological constraints that limited the capacity of militaries to fully utilize the “license to kill” afforded to them by IHL. Such a violence-enhancing effect can become even more dramatic in cases where other restraining factors are less effective. The upshot of our analysis is that the implicit assumption that IHL would be applied in a context of …

Symposium—Introduction, Russell Buchan

International Law Studies

In March 2025 the University of Reading and the U.S. Naval War College convened a workshop at the University of Reading in the United Kingdom to examine the application of the jus ad bellum, jus in bello, and international criminal law to the use of military AI. This is the introduction to the symposium, published as Volume 107 of International Law Studies.

Assessing The Role Of Ai In Determining The Necessity And Proportionality Of The Exercise Of Self-Defense Against An Armed Attack, Marco Roscini

International Law Studies

This article explores whether artificial intelligence (AI) constitutes an asset or rather a challenge in assessing the necessity and proportionality of a State’s response to an armed attack in the context of self-defense. Two central arguments are advanced. First, while AI may assist in detecting incoming threats of armed attacks, abstract and highly context-driven notions like necessity and proportionality would be very difficult to encode into algorithms. Second, even assuming that this were possible, relying on AI to determine the necessity and proportionality of a self-defense response would present as many challenges as it does advantages and, therefore, should be …

Artificial Intelligence And The Prohibition On The Use Of Force: Intention And Causation, Russell Buchan

International Law Studies

This article explores the application of Article 2(4) of the United Nations Charter to AI-enabled systems that carry out unintended engagements involving the use of force. First, it analyzes whether State responsibility for a breach of the prohibition on the use of force is defined in subjective or objective terms. Most commentators maintain that a State must intend to use force against the victim State in order for the prohibition to apply. However, through an examination of State practice, this article demonstrates that the prohibition is based on objective responsibility. Second, this article assesses whether a State must cause the …

Artificial Intelligence And The “Armed Attack” Threshold In International Law, Katie A. Johnston

International Law Studies

This article argues that the deployment of artificial intelligence, even in its strong fully autonomous form, does not have significant consequences for the application of the jus ad bellum framework, and in particular the armed attack threshold. As with all new weapons technologies, the deployment of artificial intelligence in the resort to force requires consideration of what “imminence” means in this context. However, artificial intelligence is fundamentally a means of making decisions to resort to force or contributing to the reasons for which such decisions are made by humans. Unlike the jus in bello, the jus ad bellum is …

Classification Of The Armed Conflicts In The Near East, Marco Sassòli

International Law Studies

This article explores the proper classification of Israel’s current conflicts with Hamas and Hezbollah as international or non-international armed conflicts. It discusses the different possibilities of how the international humanitarian law of international or non-international armed conflict applies to those conflicts and whether and to what extent the international humanitarian law of military occupation applies to the conduct of Israel Defence Forces in the Gaza Strip and Lebanon. It also explains why the proper classification of the conflicts still matters and is not only an intellectual exercise for scholars or students. While every conflict has its specifics, the article deals …

Safeguarding Submarine Cables And Pipelines In Times Of Peace And War, Raul (Pete) Pedrozo

International Law Studies

Incidents involving damage to undersea infrastructure illustrate the vulnerability of submarine cables and pipelines. While damage can occur accidentally in peacetime, recent incidents suggest cables and pipelines are being systematically targeted and that the resulting damage is not accidental or the result of poor seamanship. Most undersea infrastructure can also be attacked as a military objective in wartime. Peacetime adversaries or opposing belligerents during an armed conflict can easily damage undersea infrastructure to further their political, strategic, or wartime objectives. These incidents also highlight the inadequacy of coastal State authority under international law to take measures against foreign-flagged vessels intentionally …

Maritime Incidents In The South China Sea: Measures Of Law Enforcement Or Use Of Force?, Aurel Sari

International Law Studies

China has sought to extend its control over the South China Sea at the expense of neighboring countries. In pursuing its goals, Beijing adopts a “power and law” approach, claiming extensive territorial and maritime rights in contravention of the UN Convention on the Law of the Sea and asserting these rights through coercive action in disputed waters. A key element of China’s strategy involves the use of coast guard and maritime militia vessels in an effort to portray its operations as measures of law enforcement, rather than displays of coercive power.

This article argues that the Chinese narrative of law …

Cyberspace And The Jus Ad Bellum: The State Of Play, Michael N. Schmitt, Anusha S. Pakkam

International Law Studies

This article examines how States are interpreting one aspect of the international law governing cyber activities, the jus ad bellum. The article focuses on two issues: (1) the prohibition on the use of force found in Article 2(4) of the UN Charter, and (2) the right of self-defense in Article 51. The critical unsettled question regarding the first issue is the threshold at which a hostile cyber operation can be characterized as a “use of force” subject to the prohibition of Article 2(4). Concerning the second issue, a number of unresolved questions plague the application of the right of …

Benchmarks For Reducing Civilian Harm In Armed Conflict: Learning Feasible Lessons About Systemic Change, Peter Margulies

Law Faculty Scholarship

No abstract provided.

Aid And Assistance As A “Use Of Force” Under The Jus Ad Bellum, Michael N. Schmitt, W. Casey Biggerstaff

International Law Studies

Although the prohibition of the use of force is a cornerstone of international law, our understanding of what constitutes a “use of force” under Article 2(4) of the UN Charter nonetheless continues to evolve. While the term was traditionally understood to mean armed force, emerging interpretations are expanding our understanding of the prohibition’s breadth. The Charter’s text, travaux préparatoires, and subsequent interpretations and practice by States, reinforced by the persuasive reasoning of the International Court of Justice, all confirm that the notion of force extends to indirect force, which includes military support provided to parties to a conflict. Yet, to …

Some Reflections On The Threshold For International Armed Conflict And On The Application Of The Law Of Armed Conflict In Any Armed Conflict, T.D. Gill

International Law Studies

This essay discusses the threshold of application of international humanitarian law (IHL) in both international (IAC) and non-international armed conflicts (NIAC). In relation to IAC it questions whether the International Committee of the Red Cross (ICRC) “first shot” approach is the most appropriate, since it opens the way for the intensification of conflicts beyond what is necessary in relation to relatively minor armed incidents and argues that the humanitarian protection clauses of IHL should be separated from the rules governing hostilities and makes a case for the application of ad bellum considerations of necessity and proportionality to act as a …

International Child Law And The Settlement Of Ukraine-Russia And Other Conflicts, Diane Marie Amann

International Law Studies

The Ukraine-Russia conflict has wreaked disproportionate harms upon children. Hundreds reportedly were killed or wounded within the opening months of the conflict, thousands lost loved ones, and millions left their homes, their schools, and their communities. Yet public discussions of how to settle the conflict contain very little at all about children. This article seeks to change that dynamic. It builds on a relatively recent trend, one that situates human rights within the structure of peace negotiations, to push for particularized treatment of children’s experiences, needs, rights, and capacities in eventual negotiations. The article draws upon twenty-first century projects that …

Double Classification Of Non-Consensual State Interventions: Magic Protection Or Pandora’S Box?, Pauline Lesaffre

International Law Studies

The classification under international humanitarian law of certain cross-border armed conflicts against an organized armed group remains controversial. More specifically, cross-border armed conflicts resulting from a non-consensual State intervention, such as the United States’ intervention in Syria (without Syrian consent) against the Islamic State, still divide legal scholarship regarding their appropriate classification. One theory argues for a single classification of non-international armed conflict between the intervening State and the organized armed group; another theory relies on a double classification of non-consensual State interventions, adding to the non-international armed conflict an international armed conflict between the intervening State and the territorial …

Islamist Terrorism And The Classical Islamic Law Of War, Joseph Hoelz

International Law Studies

Islamist terrorists have had a large influence on U.S. foreign and domestic policy for more than twenty years, and yet policy makers, legal practitioners, and the public know very little about what motivates these violent extremist organizations. A primary unifying principle among the various Islamist terrorist groups is their desire to return to a religiously ordered State, justified and based upon their interpretation of the Shari’a, or Islamic law. This article explores the Islamist terrorist interpretation of Shari’a law and how it generally contradicts that of mainstream Islamic scholars. The article begins with a review of the primary and secondary …

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 …

Booty, Bounty, Blockade, And Prize: Time To Reevaluate The Law, Andrew Clapham

International Law Studies

This article considers the so-called belligerent rights of States in times of war. In particular it focuses on booty of war, blockade, and the capture of merchant ships and their cargo. It is suggested that, while the rules may not often be applied today, they nevertheless continue to exert a certain influence, contributing to confusion about the boundaries of the legitimate use of force and a blurring of the distinction between military objectives and civilian objects.

Considering that the UN Charter has outlawed the use of force, the article also questions why such rules concerning capture should continue to have …

The International Law Of Prolonged Sieges And Blockades: Gaza As A Case Study, Eyal Benvenisti

International Law Studies

In 2007, after Hamas’ takeover of the Gaza Strip, the area was subjected to an Israeli land siege, complemented in 2009 by a sea blockade. Since then, the already-dire living conditions in the Strip have declined consistently and the area’s dependence on external aid has grown. This essay examines the duties of a military power in imposing what is effectively a years-long confinement of people and outlines a general argument for expanding the obligations of a party that imposes a prolonged siege or blockade. I consider these obligations in light of three potentially relevant legal frameworks: the law of occupation; …

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 …

Legal Reviews Of War Algorithms, Tobias Vestner, Altea Rossi

International Law Studies

States and scholars recognize legal reviews of weapons, means or methods of warfare as an essential tool to ensure the legality of military applications of artificial intelligence (AI). Yet, are existing practices fit for this task? This article identifies necessary adaptations to current practices. For AI-enabled systems that are used in relation to targeting, legal reviews need to assess the systems’ compliance with additional rules of international law, in particular targeting law under international humanitarian law (IHL). This article discusses the procedural ramifications thereof. The article further finds that AI systems’ predictability problem needs to be addressed by the technical …

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 …

Israel’S Perspective On Key Legal And Practical Issues Concerning The Application Of International Law To Cyber Operations, Roy Schöndorf

International Law Studies

The speech given by the Israeli Deputy Attorney General (International Law) at the Naval War College’s event on “Disruptive Technologies and International Law” sets out, for the first time, Israel’s position on the application of international law to cyber operations. Consistent with the position taken by the vast majority of States thus far, Israel considers that international law applies to such operations. The speech stresses that questions pertaining to the identification and application of relevant legal rules remain, given the profound differences between the cyber domain and traditional domains of warfare—land, sea, and air. Therefore, in Israel’s view, a cautious …

Encirclement, Deprivation, And Humanity: Revising The San Remo Manual Provisions On Blockade, Tom Dannenbaum

International Law Studies

Among the most pernicious trends in contemporary armed conflict is the return of mass starvation in war, in some cases as its primary source of human suffering. This has prompted a renewed focus on the relevant rules of international humanitarian law (IHL). On some issues, there is relative consensus. On the issue of deprivation by encirclement, however, there is confusion.

Some have questioned whether the prohibition on the starvation of civilians as a method of warfare applies to encirclements at all, particularly in the naval context. Others have interpreted the prohibition vanishingly narrowly. In contrast to the more extreme of …

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 …

Autonomous Cyber Weapons And Command Responsibility, Russell Buchan, Nicholas Tsagourias

International Law Studies

Autonomous cyber weapons have made their way onto the battlefield, raising the question of whether commanders can be held criminally responsible under command responsibility when war crimes are committed. The doctrine of command responsibility has a long history in international criminal law and comprises three core elements: the existence of a superior-subordinate relationship, the commander’s knowledge of the crime, and the commander’s failure to prevent or repress the subordinate’s criminal actions. This article unpacks the content of these elements and applies them to autonomous cyber weapons by treating them as being analogous to soldiers since they operate within an organized …

The Human Dimension Of Peace And Aggression, Chiara Redaelli

International Law Studies

Since the adoption of the Charter of the United Nations, the current international legal framework has drastically changed. In its traditional understanding, aggression is “the supreme international crime” aimed at protecting sovereignty and the territorial integrity of states. On the other hand, the U.N. Charter endorses an understanding of peace in the negative sense, that is, as mere absence of war. As human rights have gained momentum, they have helped reshape the legal landscape, a phenomenon referred to as the humanization of international law. How do peace and aggression fit within the humanized legal framework? This article will investigate the …

Autonomy And Precautions In The Law Of Armed Conflict, Eric Talbot Jensen

International Law Studies

Already a controversial topic, legal debate and broader discussions concerning the amount of human control required in the employment of autonomous weapons—including autonomous cyber capabilities—continues. These discussions, particularly those taking place among States that are Parties to the 1980 Certain Conventional Weapons Convention, reveal a complete lack of consensus on the requirement of human control and serve to distract from the more important question with respect to autonomy in armed conflict: under what conditions could autonomous weapons “select” and “attack” targets in a manner that complies with the law of armed conflict (LOAC).

This article analyzes the specific LOAC rules …

The Interplay Of International Obligations Connected To The Conduct Of Others: Toward A Framework Of Mutual Compliance Among States Engaged In Partnered Warfare, Berenice Boutin

International Law Studies

This article examines international obligations that arise in relation to the conduct of other States, and analyzes how they apply and interact in the context of partnered warfare. It investigates rules of State responsibility relevant to the context of partnered warfare, as well as primary norms that impose obligations connected to the conduct of others. In essence, they consist of obligations not to actively help to or to blindly let others do what a State would not do itself. It is argued that, taken together, these rules form the contour of an overarching framework of mutual compliance among States cooperating …