"Martyr me” — that has been the challenge by Khalid Sheikh Mohammed, the alleged mastermind of 9/11, since he first appeared publicly in a Guantánamo court in June. Judging by his attempt to make a guilty plea yesterday, he and the Bush Administration have one thing in common: they want his trial — or simply, sentencing — to go ahead as soon as possible.

That might be convenient for Barack Obama, even though it is an offence against the principles of a fair trial which he has promised to uphold in his attacks on the Guantánamo policies. But the case may well spill into his term and present him with messy decisions when he wanted to take a simple moral stand.

Lacking the capture of Osama bin Laden, the trial of Mohammed and four others is the best the Bush team can do to display success in the 9/11 hunt. But yesterday’s hearings show why the camp and “military commissions” (special new courts for the trials) prompted such criticism of the US.

The first charge against Guantánamo is that the US has used it to detain hundreds without trial, denying them historic rights to challenge captivity. Until Mohammed and a dozen others arrived in the past two years, it held no one obviously more senior than bin Laden’s driver.

Mohammed is one of only a handful even to be charged. But the commissions represent an unfair trial, depriving defendants of rights they would have in US military or criminal courts. There, evidence from torture is inadmissable, but the commissions have simply reinterviewed prisoners — such as Mohammed, who were tortured, by most definitions — to claim that the evidence is “clean”. Yesterday also showed that crucial questions remain unsettled after seven years, such as whether prisoners can fire their Pentagon lawyers, denying themselves representation.

If the commission accepts the guilty plea, passes the death sentence, and Mohammed is executed before January 20, then he will get his wish to be a martyr. But if not, then Obama will find that shutting the camp is the trivial decision. The hard one will be whether to overturn a death sentence on the self-proclaimed architect of 9/11, and then to press ahead with the trial, in US courts, of a man tortured by US agents.

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