They could have gotten a lot of information from the Detroit bomber....

They should have treated him like a combatant...

The chance to secure crucial information about al-Qaeda operations in Yemen was lost because the Obama administration decided to charge and prosecute Umar Farouk Abdulmutallab as an ordinary criminal, critics say. He is said to have reduced his co-operation with FBI interrogators on the advice of his government-appointed defence counsel.

The potential significance became chillingly clear this weekend when it was reported that shortly after his detention, he boasted that 20 more young Muslim men were being prepared for similar murderous missions in the Yemen.

The lawyer for the 23-year-old Nigerian entered a formal not guilty plea on Friday to charges that he tried to blow up a Detroit-bound airliner on December 25 – even though he reportedly admitted earlier that he was trained and supplied with the explosives sewn into his underwear by al-Qaeda in the Arab state.

"He was singing like a canary, then we charged him in civilian proceedings, he got a lawyer and shut up," Slade Gorton, a member of the 9/11 Commission that investigated the Sept 2001 terror attacks on the US, told The Sunday Telegraph.

"I find it incomprehensible that this administration is treating terrorism as a law enforcement issue. The president has finally said that we are at war with al-Qaeda. Well, if this is a war, then Abdulmutallab should be treated as a combatant not a criminal."

Abdulmutallab could have been held and interrogated in military custody under existing US legislation before a decision was taken whether to charge him before a military tribunal or a civilian court, according to Michael Mukasey, the last Attorney General under President George W Bush.

Mr Mukasey argues that it was crucial to gain intelligence from him immediately as details about locations, names and other plots is subject to rapid change. For the same reason, he dismissed the argument by John Brennan, Mr Obama's chief counter-terrorism adviser, that investigators will garner valuable data during any plea-bargaining talks.

"He certainly should know that the kind of facts that Abdulmutallab might be expected to know have a shelf life that is a lot shorter than the plea bargaining process," he wrote in the Wall Street Journal last week.