INTRODUCTION
The Iran-Israel war has been a convoluted story with a history of terrorist attacks, proxy wars, and shifting alliances. If we track down the history of relations between Iran and Israel, it has been a tumultuous one. Initially, both nations shared a harmonious relationship, with Iran recognising the sovereignty of Israel in 1948 and constructing strategic alliances in the initial years. But there was a strategic shift in the trajectory of Iran-Israel’s relations following the Islamic Revolution of 1979—this paved the way for animosity between the two Middle Eastern countries.
The recent Israeli airstrikes have been in response to the development of nuclear facilities in Iran. Israel, seeing the Iranian development as a threat, launched missiles to thwart the Iranian plans. However, the other side retaliated, sparking a war between the two. The situation escalated with the recent entry of the US. The US, which initially intervened as a mediator, ultimately became a participant in the war.
INTERNATIONAL LAW APPLICABILITY
When viewed through the prism of International Law, the legal framework applicable to this war is the UN Charter, along with international humanitarian law. The discussion predominantly focuses upon the fact that the war is in a direct violation of Article 2(4) of the UN Charter, under which states are expressly prohibited from resorting to “the threat or use of force against the territorial integrity or political independence of any state”.[1] The only exception to this is mentioned in Article 51[2] Of the UN Charter, which lists out Self-Defence or authorisation by the UN Security Council as a valid exception.
Another point to be considered is that of Jus ad bellum, which addresses the lawfulness of the initiated armed conflict, and Jus in Bello, which governs the conduct of the parties during an armed conflict, disregarding whether the initial hostilities were lawful. The doctrine of Jus ad bellum lists out the conditions under which use of force can be deemed as lawful— necessity,,, proportionality and existence of an armed attack or imminent threat.
Jus ad bellum (law on the use of force) or jus contra bellum (law on the prevention of war) seeks to limit the resort to force between states.[3] It promotes the idea of just war wherein the UN Charter supports only one cause—self-defence. The key considerations of this doctrine are—just cause, wherein only a cause which is lawful and just in nature can be considered, but its interpretation varies from case to case. The second consideration is the last resort, which specifies that war should be adopted by a nation only when all other options have been exhausted. War should not be the first reaction to any global tensions. The third consideration is proportionality. The use of force should be proportional to the threat perceived or faced, and the harm caused should not be more than the good achieved.
Jus in bellum, on the other hand, means right conduct in war. It reinforces the principle of human rights and upholds that war should be fought, keeping in mind the rights of people involved in the war and the people of the country.[4] Just war theory sets a moral framework for warfare and goes against the notion that “everything is fair in war”. The principles of humanitarian law are applied in times of conflict, and they attempt to regulate the actions of military forces. The regulations governing warfare seek to preserve human life and fundamental rights, and ensure to maintain the level of violence in a war is maintained. They aim to prevent total war, where the absence of discrimination and proportionality removes key restraints on violence.
Furthermore, an examination of International Law also leads to the Caroline Test. It is a principle of customary international law that defines conditions under which a state can lawfully use force in self-defence against an immediate threat. It necessitates the pre-existence of an instant, overwhelming threat, leaving no time for deliberation. This standard was established following the 1837 Caroline affair, where British forces attacked and destroyed an American ship, the Caroline. The key aspects of the applicability of this test are—an imminent threat, necessity of the use of force, leaving no choice, and proportionality of force to the threat.
LEGAL ANALYSIS THE WAR JUSTIFIED?
The central debate revolves around whether Israel’s actions conform to the international legal standards rooted in jus ad bellum. The Israeli government puts forth the contention that Iran’s recent nuclear development posed an immediate threat to Israel, keeping in mind the Hamas attack on Israel in the recent past. However, the international community remains divided on this claim.
Based on the Caroline test, the use of force is only justified where an attack is imminent—a condition characterised by necessity, overwhelming circumstances, and no other alternative. The Israeli justification, citing Iran’s alleged intent to develop nuclear weapons “within months,” does not, from a legal perspective, meet this threshold since Iran has yet to produce a nuclear weapon and has not taken overt acts of aggression. Thus, Israel’s contention cannot be viewed from a just perspective.
Moreover, concern persists over Israel’s strikes violating the principles of International Humanitarian Law (IHL), particularly due to the injury of civilians or bombing of a nuclear site. IHL mandates differentiation and proportionality[5], requiring parties to distinguish between attackers and civilians and to avoid excessive damage. The targeted destruction of nuclear facilities could result in dangerous outcomes, which raises legal eyebrows along with ethical questions over the legitimacy of such attacks.
On the other hand, legal constructions consider Israel’s actions as part of a broader self-defence in response to ongoing proxy attacks by Iran’s aligned groups like Hezbollah, Hamas, and the Houthi rebels. Scholars argue that these proxy wars could fulfill the effective control standard of the Nicaragua case.[6] Thus providing legal justification for Israel’s measures.
Nonetheless, the evidence of “effective control” remains contested, and the absence of a clear-cut imminent attack complicates this legal defence.
THE WAY FORWARD: NAVIGATING GEOPOLITICS AND LAW
The Israel-Iran conflict is a great example of the tension between national security interests and the constraints of International Law. The primary path to resolution involves reinforcing adherence to vital principles of necessity and proportionality. A more sustainable approach to managing conflict lies in diplomatic engagement, confidence-building initiatives, and strong verification mechanisms, rather than in unilateral military action.
A clarification must be given by the international community on the scope of pre-emptive use of force, maybe through a renewed UN Security Council. The Caroline doctrine’s filter of imminence remains central; broad interpretations risk enabling a “license to kill” based on conjecture, threatening global stability.
Furthermore, the persistent proxy warfare in the region underscores the fundamental importance of maintaining accountability and respecting state sovereignty. Countering Iran’s support for militant proxies demands a multifaceted approach centred on diplomatic solutions, precisely calibrated economic sanctions, and the development of comprehensive regional security frameworks. However, implementing such measures requires careful consideration to avoid exacerbating tensions or triggering unintended consequences.
Most critically, the international community must ensure uniform adherence to established legal norms regarding the use of force. When these principles are violated, it weakens the entire structure of global governance, emboldening states and non-state actors alike to bypass legal constraints designed to limit hostilities and preserve stability. To curb further escalation, reinforcing international legal institutions and enhancing their enforcement capabilities must remain a top priority.
CONCLUSION
The Iran-Israel conflict tests the applicability and enforceability of the international legal order. While Israel’s claims of an immediate threat face scrutiny, the broader challenges lie in making international laws applicable to all nations and ensuring that they follow those laws. Upholding norms such as necessity, proportionality, and immediacy under international law is crucial, not just for legal consistency but for maintaining global stability. As the conflict unfolds, it remains imperative for the international community to navigate these legal boundaries judiciously, prioritizing diplomatic solutions over brute force and ensuring accountability to uphold the rule of law.
Author(s) Name: Gannavarpu Rajlakshmi (National Law Institute University, Bhopal)
References:
[1] Charter of the United Nations, Art. 2(4), (adopted 26 June 1945, entered into force 24 October 1945).
[2] Charter of the United Nations, Art. 51, (adopted 26 June 1945, entered into force 24 October 1945).
[3] ‘Jus ad bellum and jus in bello’ (International Committee of the Red Cross, 22 January 2015) <https://www.icrc.org/en/document/what-are-jus-ad-bellum-and-jus-bello-0> accessed 22 June, 2025.
[4] Eliav Lieblich, ‘The Humanization of Jus ad Bellum: Prospects and Perils’ (2021) 32 The European Journal of International Law 579, 580.
[5] Hitoshi Nasu, ‘Targeting a Satellite: Contrasting Considerations between the Jus ad Bellum and the Jus in Bello’ (2022) 99 INT’L L. STUD. 142.
[6] The Republic of Nicaragua v United States of America, (1986), ICJ Reports 1986, p. 14.
