For much of President Barack Obama’s first year in office, his national security team worked to devise a secure plan to send dozens of Yemeni detainees held at Guantanamo Bay, Cuba — the largest single group at the prison camp — home to Yemen, perhaps to a rehabilitation programme. Then came the Christmas Day airliner bombing attempt, which was planned in Yemen, and the President put all transfers there on hold.

Since November, the administration had been preparing to move the highest-profile Guantanamo prisoners — Khalid Shaikh Mohammed and four accomplices accused of plotting the September 11, 2001, attacks — to Manhattan for a federal criminal trial.

But overwhelming opposition from New York politicians concerned about costs, disruptions and security has the Justice Department scrambling to come up with a Plan B, even as Congress threatens to block money to pay for a criminal 9/11 trial altogether. That could force the administration to revive the very option that the President and Attorney General Eric H. Holder Jr. had rejected: military commissions at Guantanamo for the 9/11 plotters.

“It’s obviously proven a lot more difficult than a lot of us expected to close Guantanamo,” said Sarah E. Mendelson of the Centre for Strategic and International Studies in Washington, who has studied the issue intensively. She called the turnaround of Mayor Michael R. Bloomberg and other New York officials “disappointing” and the costly security plan they proposed for Manhattan excessive, given the major al-Qaeda trials held there in the past with far less disruptive procedures.

For some who have always advocated military commissions for the 9/11 plotters, the demise of the Manhattan plan simply proved their point. “It just shows what a dumb idea it was in the first place,” said Sen. Lindsey Graham in an interview on Thursday. Graham plans to reintroduce legislation in a few days to block criminal trials for the 9/11 suspects altogether.

A similar bill is already pending in the House. Two Democratic Senators, Blanche Lincoln of Arkansas and Jim Webb of Virginia, joined several Republican colleagues last week in coming out against criminal trials for the Qaeda plotters, raising opponents’ hopes that Congress could make the hunt for a new 9/11 courthouse moot.

“The attacks of 9/11 were acts of war, and those who planned and carried out those attacks are war criminals,” the group of six Senators wrote in a letter to the Attorney General. They said any American venue for a trial would become a terrorist target, and that military commissions were the proper way to bring terrorists to justice. © 2010 The New York Times News Service

More In: Comment | Opinion