The Government’s decision to ask the US to send back five former British residents held at Guantanamo Bay is the right one. But there is an air of grandstanding about it – with ministers expecting plaudits for berating the superpower about the infamous detention camp, when the request is the product of months of talks between the two countries, and is just what the US wants.

The Government also skirts around its own unresolved policies; it rightly criticises the US for using Guantanamo to put some categories of terrorist suspects beyond the conventional legal frameworks, but it has not firmly decided how to treat similar cases itself.

The joint statement by David Miliband, the Foreign Secretary, and Jacqui Smith, the Home Secretary, asking for the return of the five men, is a clear change from the policy of Tony Blair’s Government, which took back British citizens at Guantanamo (and released them without charge), but declined to do the same for those who had merely been residents. It did not want to set precedents for accepting other countries’ nationals, officials said.

Why the change? The Government says it has shifted position because the US is now taking steps to shrink Guantanamo. But to claim a victory of principle in this way is misleading. It would be more accurate to say that the US has called Britain’s bluff.

For two years a series of ministers, culminating in Blair himself, criticised Guantanamo for offending shared values, including the rule of law and the right to a fair trial. They were on good ground on the three points that have made Guantanamo so contentious internationally: the lack of adequate means of distinguishing suspects from ordinary people scooped up near a battlefield; indefinite detention without trial; and for the small minority charged, the use of special, new “military commissions” to try them.

The US, while nodding to these complaints in last year’s Military Commissions Act, has tried to portray the rising embarrassment of Guantanamo as a practical problem that other countries could help it to solve, if they chose. It lamented that it would get rid of the inmates if it could only find homes abroad for these undesirables, many unwanted in their own countries.

It looked hard at Britain when it made that point, the more so as ministers’ criticism became louder. For the past year the public efforts of David Johnson, until last month the second-in-command at the US Embassy in London, seemed devoted to the advocacy of the case.

The pressure worked, finally, in getting Britain to reverse its position on taking back the residents. But that does not make it a good argument, and Britain can hardly claim a moral victory. The US has not jettisoned the policies that made Guantanamo controversial. It has not set aside the principle of detention without trial for some suspects, and although it has amended the worst aspects of the military commissions, lawyers for the inmates argue that they do not offer the protections of a conventional military trial.

Above all, it has sidestepped the charge that it should have taken more care about picking up suspects in the first place, and provided them, and itself, with a better way of assessing who they were. The “combatant status review tribunals” of Guantanamo were its attempt to meet the requirements of the Geneva Conventions that it find an adequate way of sifting its captives. But they have been fiercely criticised by defence lawyers for failing to provide a proper way to challenge supposed evidence.

The US has said nothing about the evidence against the five British residents, and despite years of detention has not charged them. We can assume that Britain is aware of any evidence against them and can already judge whether they present a threat, given that when British citizens were sent back from Guantanamo, in 2004 and 2005, it knew by the time of their flight home that it could release them.

If it does so again, that will be a slap at the US, although if there is no case against them, a richly deserved one. And if it feels they might be a threat but lacks adequate evidence? That will take the Government into the unsettled waters of Britain’s control orders. But that is an area it needs to tackle in any case, and it is better that it does it by rejecting, as a starting point, the principles that have made Guantanamo offensive.

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