Trying Mohammed in military court would mark a further political retreat from Holder’s announcement last year that Mohammed and the four other Sept. 11 suspects now held at the US military prison at Guantanamo Bay, Cuba, would be tried in federal court in New York.

The Obama administration is trying to head off a possible vote in the Senate that could stop any terror suspects held at Guantanamo from being brought to the United States to face a civilian trial. Senator Lindsey Graham, a South Carolina Republican, is offering such legislation, after losing a vote last year on the issue.

“These Al Qaeda terrorists are not common criminals,’’ Graham said yesterday in the Republicans’ weekly radio and Internet address. “A civilian trial of hard-core terrorists is unnecessarily dangerous and creates more problems than it solves.’’

At stake is the public perception of the administration’s handling of national security, already shaken last year by strong congressional opposition to transferring any Guantanamo detainees to American soil.

A Hill defeat over the trial issue could embolden the GOP minority to raise national security concerns in the midterm elections later this year.

“Military tribunals are the best way to render justice, win this war, and protect our nation from a vicious enemy,’’ said Graham.

The prospect of such a vote could be a test of how many moderate Democrats have abandoned Obama on the issue. (Emphasis added)