Why Iran’s Missile Launches and the U.S. Retaliatory Strikes Demand Scrutiny of International Self‑Defence and State Responsibility Rules

On a recent occasion Iran reportedly launched a coordinated salvo of ballistic missiles and unmanned aerial vehicles directed toward the sovereign territories of Kuwait and Bahrain, thereby initiating a hostile act that expanded the ongoing regional hostilities in the Persian Gulf vicinity. The defensive air‑space authorities of both Kuwait and Bahrain are said to have engaged the inbound threats with their respective air‑defence systems, resulting in the interception and neutralisation of several of the Iranian‑launched projectiles and drones, an operational response aimed at averting potential casualties and infrastructural damage on their soil. Concurrently the United States military is reported to have intercepted additional Iranian missiles and drones that were allegedly targeting the strategically vital Strait of Hormuz and allied forces operating in the area, and in retaliation it conducted strikes against Iranian radar installations, thereby extending the kinetic exchange beyond the immediate theatres of Kuwait and Bahrain. These sequential events have escalated tensions between Tehran and Washington, reflecting a broader pattern of confrontation in the region and prompting legal scholars and policymakers to contemplate the applicability of international legal doctrines concerning the use of force, state responsibility, and the right of self‑defence under the United Nations Charter. International observers have noted that the interception of the missiles and drones by Kuwait and Bahrain may invoke the principle of inherent right of self‑defence articulated in Article 51 of the Charter, yet the proportionality and necessity of the subsequent US strikes on Iranian radar sites remain subjects of debate within the legal community. Furthermore, the cross‑border nature of the attacks raises questions regarding the territorial jurisdiction of the affected states, the permissibility of defensive actions conducted in international airspace, and the potential avenues for recourse before the International Court of Justice or a United Nations‑mandated fact‑finding mission.

One question is whether the missile launches directed at Kuwait and Bahrain constitute a breach of the prohibition on the use of force under Article 2(4) of the United Nations Charter, given that the act involved armed projectiles launched from Iranian territory toward the sovereign airspace of other states without prior United Nations Security Council authorization. The answer may depend on whether the attacks can be characterised as an armed attack triggering the right of self‑defence for the victim states, a determination that traditionally requires an assessment of the scale, immediacy and effect of the use of force on the territorial integrity or political independence of the targeted nation. Perhaps the more important legal issue is the legality of the United States’ retaliatory strikes on Iranian radar installations, which raises the question of whether a state may exercise anticipatory self‑defence in response to an ongoing aerial assault that has not yet materialised within its own territory, a doctrine that remains contentious and is subject to the restrictive criteria of necessity and proportionality.

Perhaps a court would examine the proportionality of the US response by comparing the military advantage sought through the destruction of radar sites against the potential escalation of hostilities, an inquiry that would involve weighing the immediacy of the threat against the broader objective of preventing further attacks on allied forces and commercial navigation through the Strait of Hormuz. Perhaps the procedural significance lies in the requirement that any exercise of self‑defence, whether by Kuwait, Bahrain or the United States, be reported to the Security Council promptly under Article 51, a procedural step that ensures transparency and allows the Council to take further measures, and failure to comply could give rise to allegations of unlawful use of force. Perhaps the statutory question is whether the domestic legislation of the United States authorising the use of force abroad, such as the Authorization for Use of Military Force or specific executive orders, satisfies the international requirement that any resort to force be grounded in a legal basis recognised by the international community, an issue that may be scrutinised in any subsequent domestic or international judicial review.

Perhaps the legal position would turn on the principles of state responsibility, whereby Iran could be held liable for internationally wrongful acts caused by the missile launches, obligating it to cease such conduct, make reparations, and possibly face counter‑measures, a conclusion that would typically be affirmed by an international adjudicative body or through diplomatic negotiations under the framework of the International Law Commission’s Articles on State Responsibility. A fuller legal conclusion would require clarity on whether Kuwait and Bahrain have undertaken any formal diplomatic protests or sought to invoke the right of self‑defence in a manner that satisfies the requirement of necessity, thereby influencing the scope of permissible defensive actions and the legitimacy of any subsequent claims for restitution or compensation. The safer legal view would depend upon whether the United States can demonstrate that its strikes were proportionate and necessary to neutralise an imminent threat to its forces and allied shipping, a determination that could affect the admissibility of any counter‑measure claims by Iran and shape the future conduct of diplomatic engagement in the Gulf region.

In sum, the intersecting issues of the legality of Iran’s missile and drone attacks, the right of self‑defence claimed by Kuwait, Bahrain and the United States, the proportionality and reporting obligations under the United Nations Charter, and the mechanisms for state responsibility collectively illustrate the complex tapestry of international legal norms that govern the use of force, and they underscore the need for careful legal scrutiny before any escalation is deemed permissible. Any future diplomatic or legal proceedings, whether before the International Court of Justice, an arbitral tribunal, or a United Nations fact‑finding mission, will likely grapple with the evidentiary burden of establishing the immediacy of the threat and the proportionality of the response, thereby shaping the development of customary international law concerning anticipatory self‑defence. Thus, states in the region, as well as international legal scholars, will monitor closely how the interplay of national security imperatives and international legal constraints unfolds, recognizing that the resolution of these questions will have enduring implications for the stability of the Gulf and the credibility of the global non‑proliferation and peace‑security architecture.