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Iran Conflict 2026
22MAR

UK attorney general: war unlawful

3 min read
05:50UTC

The UK attorney general advised that the US-Israeli campaign breaches international law. Starmer opened British bases for it anyway.

ConflictDeveloping
Key takeaway

Unlike Iraq 2003, the UK government has acted against — not around — its chief legal officer's formal advice.

Lord Hermer KC, the UK attorney general, advised the government that the US-Israeli military campaign against Iran does not accord with international law 1. That assessment shaped Prime Minister Starmer's initial refusal on 28 February to grant Washington access to any British military facilities 2. Starmer reversed within 48 hours, authorising "specific and limited defensive operations" from RAF Fairford and Diego Garcia while refusing RAF Akrotiri in Cyprus for offensive strikes. A former Director of Public Prosecutions now facilitates operations his own chief law officer assessed as unlawful.

Chatham House published analysis arguing the distinction between defensive and offensive base use "blur[s] the line between lawful self-defence and unlawful war on Iran" 3. Under Article 16 of the International Law Commission's Articles on State Responsibility, a state that knowingly aids another's internationally wrongful act bears international responsibility — regardless of how it categorises its contribution. The label "defensive" does not insulate London if the underlying campaign is assessed as unlawful.

The UK faced a version of this in 2003. Attorney General Lord Goldsmith's advice on the Iraq invasion — initially equivocal, later firmed up under political pressure — consumed the Chilcot Inquiry for seven years and destroyed the Blair government's credibility on the use of force. Starmer's legal exposure is sharper: Goldsmith's advice was ambiguous; Hermer's, as reported by Middle East Eye, is not 4.

Iran had warned the UK on Thursday that permitting US access to British bases made Britain "a participant in aggression." Within hours of London confirming that access, two intermediate-range ballistic missiles were fired at Diego Garcia — the first Iranian weapons aimed at British sovereign territory in this conflict. One malfunctioned; the other was intercepted; no damage resulted. Britain is now the only European state absorbing direct Iranian retaliatory fire, while the Coalition of Hormuz-statement signatories has grown from seven to 22 without a single warship deployment.

Deep Analysis

In plain English

Every British government has a lawyer called the Attorney General who advises whether government actions are legal under international law. In 2003, the Attorney General eventually said the Iraq War was legal — so the government proceeded, and controversy centred on whether that advice was genuinely independent. This time, the Attorney General has said the operation does not accord with international law. The difference is that the government gave the US base access anyway, without the legal advice changing. This matters because it establishes a precedent that the government can act contrary to its own published legal opinion when alliance politics demand it — and because it creates a documentary record that future courts, inquiries, or parliamentary committees will find easier to work with than the contested advice trail from 2003.

Deep Analysis
Synthesis

Hermer's advice creates an evidentiary record that distinguishes the current UK position from every prior military intervention in living memory: the government acted with documented legal warning rather than despite legal uncertainty. This shifts future accountability from 'the government was misled about legality' — the Iraq template — to 'the government was told and proceeded anyway.' The Chatham House critique compounds this by arguing the defensive/offensive distinction is not merely contested but legally incoherent, potentially exposing specific ministers and officers to individual accountability under the ILC Articles on State Responsibility.

Root Causes

The structural cause is the absence of a UK War Powers Act. Unlike the US, where Congress holds constitutional declaration authority, British prime ministers can commit military assets through royal prerogative without parliamentary authorisation. This concentrates legal risk in the executive with no distributional accountability mechanism — meaning the legal advice was the only institutional check available, and it has been overridden without formal procedure.

What could happen next?
  • Risk

    ICJ or ICC proceedings against UK government officials for complicity in unlawful use of force are procedurally easier given the documented, unrevised contrary legal advice.

    Long term · Suggested
  • Precedent

    A sitting attorney general's published international law advice overridden by executive action weakens the constitutional norm that legal advice constrains royal prerogative in military matters.

    Long term · Assessed
  • Consequence

    Parliamentary opposition holds a clear legal hook for judicial review of the basing decision, given the existence of undisputed contrary attorney general advice.

    Immediate · Assessed
  • Risk

    US allies facing analogous basing pressure — Australia, Canada, Japan — may read the UK precedent as licence to override domestic legal advice under alliance pressure.

    Short term · Suggested
First Reported In

Update #44 · Trump: 48 hours to destroy Iran power grid

Chatham House· 22 Mar 2026
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Causes and effects
This Event
UK attorney general: war unlawful
The UK government's chief legal adviser assessed the US-Israeli operation as contrary to international law — advice Starmer overrode within 48 hours. The gap between legal counsel and political action parallels the Iraq War's Goldsmith controversy, while Iran's retaliatory strike on Diego Garcia within hours of the base authorisation made the consequences operational.
Different Perspectives
South Korean financial markets
South Korean financial markets
South Korea, which imports virtually all its crude oil, is absorbing the war's economic transmission most acutely among non-belligerents. The second KOSPI circuit breaker in four sessions — with Samsung down over 10% and SK Hynix down 12.3% — reflects an industrial economy unable to reprice energy costs that have risen 72% in ten days. The market response indicates Korean industry cannot sustain oil above $100 per barrel without margin compression across manufacturing, semiconductors, and shipping.
Migrant worker communities in the Gulf
Migrant worker communities in the Gulf
The first confirmed civilian deaths in Saudi Arabia — one Indian and one Bangladeshi killed, twelve Bangladeshis wounded — fell on communities with no voice in the military decisions that placed them in harm's way. Migrant workers live near military installations because that housing is affordable, not by choice. Bangladesh and India face the dilemma of needing to protect nationals who cannot easily leave a war zone while depending on Gulf remittances that fund a substantial share of their domestic economies.
Azerbaijan — President Ilham Aliyev
Azerbaijan — President Ilham Aliyev
Aliyev treats the Nakhchivan strikes as a direct act of war against Azerbaijani sovereignty, placing armed forces on full combat readiness and demanding an Iranian explanation. The response is calibrated to maximise international sympathy while stopping short of military retaliation — Baku cannot fight Iran alone and needs either Turkish or NATO backing to credibly deter further strikes.
Oil-importing nations (Japan, South Korea, India)
Oil-importing nations (Japan, South Korea, India)
The Hormuz closure is an existential threat. Japan, South Korea, and India receive the majority of their crude through the strait — they will bear the heaviest economic cost of a war they had no part in.
Global South governments (Indonesia, Brazil, South Africa)
Global South governments (Indonesia, Brazil, South Africa)
Neutrality was possible when the targets were military. 148 dead schoolgirls made it impossible — no government can explain that away to its own citizens.
Turkey
Turkey
Has absorbed three Iranian ballistic missile interceptions since 4 March without invoking NATO Article 5 consultation. Each incident narrows Ankara's political room to continue absorbing without Alliance-level response.