Unilateral Use of Force Against Iran’s Nuclear Facilities: Legal Authority, Constraints, and Consequences

(c) asserted by Er. Sarbajit Roy, Brahma University
22-June-2025 10:27 am IST, New Delhi

Er. Sarbajit Roy. (2025). Unilateral Use of Force Against Iran’s Nuclear Facilities: Legal Authority, Constraints, and Consequences.

Abstract

Recent airstrikes ordered by President Donald Trump on Iranian nuclear sites have reopened the debate on the scope of presidential war powers and the legality of using force without Congressional approval or international mandate. This article examines the legal bases under international law and U.S. domestic law that could justify—or constrain—such actions. It concludes that the strikes lack a solid legal foundation and may set harmful precedents for unilateral force in nuclear contexts.

1. International Legal Framework

1.1 The UN Charter and the Prohibition on the Use of Force

Article 2(4) of the United Nations Charter establishes a general prohibition¹:

“All Members shall refrain… from the threat or use of force against the territorial integrity or political independence of any state…”

Exceptions to this rule are narrowly defined:

• Article 51: Permits self-defense in response to an armed attack.

• Chapter VII: Grants the Security Council authority to address threats to peace².

No armed attack by Iran had occurred, nor did any Security Council resolution authorize force. Accordingly, the legality of the U.S. strikes under the UN Charter is highly questionable.

1.2 Customary International Law and the Caroline Standard

The doctrine of anticipatory self-defense, articulated in the 1837 Caroline case, requires that any threat be³:

• Instant

• Overwhelming

• Leaving no choice of means and no moment for deliberation

There is no public evidence Iran posed an imminent threat. Its nuclear facilities remained under IAEA oversight per its Non-Proliferation Treaty obligations⁴. Preventive strikes premised on hypothetical future threats are inconsistent with international law.

2. U.S. Domestic Legal Framework

2.1 The U.S. Constitution and the Separation of Powers

• Article I, Section 8: Assigns Congress the power to declare war.

• Article II, Section 2: Designates the President as Commander-in-Chief.

This framework was intended to prevent unilateral military action. Although the President may act in emergencies to repel sudden attacks, initiating offensive operations absent imminent danger or Congressional approval exceeds constitutional authority⁵.

2.2 The War Powers Resolution (1973)

Enacted to rein in executive overreach, the War Powers Resolution:

• Mandates notification of Congress within 48 hours of initiating hostilities.

• Limits unauthorized military action to 60 days without Congressional approval.

Though the Trump administration claimed it met the notification requirement, no Congressional authorization for extended hostilities has been disclosed. This raises a compliance concern under the WPR⁶.

2.3 The AUMFs of 2001 and 2002: Scope and Relevance

• 2001 AUMF: Targeted groups responsible for the September 11 attacks.

• 2002 AUMF: Authorized military action in Iraq.

Neither statute applies to Iran. Legal consensus affirms that these authorizations are outdated and insufficient to justify force against a distinct sovereign nation⁷.

“There is no credible argument that either AUMF covers offensive action against Iran.” — Congressional Research Service, 2023

3. Precedent and Global Implications

3.1 The Osirak Precedent

The 1981 Israeli strike on Iraq’s Osirak reactor was similarly preventive in nature. The UN Security Council unanimously condemned it, affirming that such preemptive attacks on sovereign nuclear sites under international supervision are unlawful under the Charter⁸.

3.2 Undermining the IAEA and the NPT Regime

Striking Iran’s IAEA-monitored facilities jeopardizes:

• The integrity of the IAEA.

• The credibility of the NPT framework.

• Global incentives for peaceful nuclear compliance.

These actions risk destabilizing multilateral arms control mechanisms and may incentivize states to pursue clandestine militarization⁹.

4. Recommendations

1. Strengthen Congressional Oversight: Repeal obsolete AUMFs and require fresh authorization for hostilities against new state actors.

2. Recommit to International Norms: Publicly affirm U.S. commitment to the UN Charter and principles governing use of force.

3. Restore IAEA Credibility: Collaborate with international partners to reinforce the IAEA’s central monitoring role.

4. Define “Imminence”: Establish transparent, reviewable standards for evaluating imminent threats under anticipatory self-defense.

5. Analysis

The U.S. airstrikes on Iranian nuclear infrastructure lack clear legal justification under both international and domestic law. They sidestep the legal mechanisms meant to govern the use of force, risking long-term damage to international norms and the rule of law. Reestablishing legal accountability is essential for preventing escalation and ensuring a rules-based international order.