UK base decision on Iran strikes tests humanitarian intervention doctrine

IRAN

With Washington preparing for possible strikes, the Government invokes legal risk – even as its own humanitarian doctrine appears to point the other way. This may carry costs for Britain’s strategic posture at a volatile moment for the international order.

BRITAIN’S refusal to allow US forces to launch potential strikes on Iran from sovereign UK air bases is intensifying scrutiny of how the Government chooses to interpret international law – and the strategic consequences that stance could carry for Britain’s influence in Washington.

The decision comes as US military aircraft continue to surge through British and European airfields in what Nato officials describe as the largest American force build-ups in the region since 2003.

Open-source flight tracking data shows dozens of US transport and refuelling aircraft landing at RAF Mildenhall, RAF Lakenheath and Prestwick, with deployments through Cyprus and southern Europe. Two Nato officials say the movements are consistent with preparations for a “significant air campaign”.

Yet claims have emerged that Sir Keir Starmer told Donald Trump during a phone call on Tuesday that the UK would not permit sovereign bases such as RAF Fairford or Diego Garcia to be used as launchpads for strikes on Iran.

Ministers have declined to comment on operational matters, but government sources indicate such use could render the UK complicit in an internationally wrongful act under the law of state responsibility.

Under that doctrine, a state that knowingly assists another in committing a wrongful act may bear responsibility. Attorney General Lord Hermer is understood to have concluded the UK should avoid that exposure.

Dr Alexander Gilder, associate professor of international law and security at the University of Reading, says the reported position rests on that principle.

“It’s the law of state responsibility that the UK is concerned that it becomes complicit in an act of wrongdoing committed by its ally,” he says.

Such determinations, he notes, are inherently interpretative.

“Most things are going to be a subjective decision of legal advisers who say, ‘We believe it, more likely than not, that there is a wrongful act being committed by the United States, and we need to be one step removed from that.’”

The UK has long maintained that humanitarian intervention can be lawful without UN Security Council authorisation – a position set out in parliamentary proceedings for more than a decade.

“The UK is one of the only countries to have a written down legal opinion that says humanitarian intervention is, in the eyes of our government, lawful under international law,” Gilder says. “That’s a controversial opinion.”

More than 35,000 Iranian civilians have been killed by the regime, according to uncorroborated internal Iranian documents.

“They could have argued that the regime is killing thousands of its own citizens and on a humanitarian basis taking action against that regime might be justified,” he says.

Instead, the Government appears to have prioritised distancing itself from potential legal exposure.

Former defence secretary Gavin Williamson says legal advice is rarely binary.

“You can get a legal decision one way or another,” he says. “It’s very easy to get a legal decision on the basis that it’s perfectly just to use those bases in preservation of human life.

“But Richard (Attorney General Lord Hermer) won’t allow it because it’s against his worldview. It’s a choice.”

Britain has previously relied on humanitarian reasoning to justify support for military action, he says, adding: “On this, for very low cost – well, for no cost at all – I think you could have at least been on the right side of history.”

Portugal, by contrast, has relied on existing bilateral agreements to allow continued US access to its facilities.

For senior defence figures, the implications extend beyond doctrine.

Former Chief of the Air Staff Air Chief Marshal Sir Michael Graydon says alliance management cannot be reduced to legal interpretation alone.

“There is a difference between legal and legitimate,” he says. “That is a political judgment.”

He adds. “If you’re not involved, you are not influencing.”

Last year Maj Gen Jason Armagost, commander of the US Eighth Air Force, described Britain’s bases as central to American reach.

Speaking at RAF Fairford, he said: “One of the things we know about the Pacific is the ‘tyranny of distance’ – you have to fly for many more hours to touch a few countries.

“The Bomber Task Force is incredibly effective in the European theatre because, for that same duration, we can almost touch the entire continent.

“From Europe, we can fly to Africa, we can fly to the Middle East. This is of incredible value.”

Air Marshal Edward Stringer, former Assistant Chief of the Defence Staff (Operations), who authorised expanded US access to RAF Akrotiri during coalition operations against ISIS, says denying access carries political cost.

“It’s technically true that Washington could strike from elsewhere,” he says. “But even if they don’t need us, refusing our facilities adds extra risk and makes strikes harder, longer and more costly.”

He adds: “What many people don’t realise is that global reach still depends on a whole range of dependable lily pads.

“When you stop this, you get cut out of discussions. Even if they’re just using your base, you have to involve people in a discussion about what you’re going to do.”

It remains unclear how far President Trump ultimately intends to go. While US movements suggest credible preparations, he may be satisfied with neutralising Iran’s nuclear facilities and ballistic missile programme, leaving regime change to internal momentum.

For Gilder, the issue is whether the Government is prepared to uphold its own doctrine.

“If you’re going to lay your stake in the ground on humanitarian intervention,” he says, “then you have to do it consistently.”

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