Updated

President Obama's inability to follow through with his pledge to close Guantanamo Bay by January may stand as the most glaring failure of his first year in office.

Despite questions about the unresolved fate of health care reform, energy legislation and other initiatives, the Guantanamo closing is a measurable promise, with a deadline, on which the administration has clearly not delivered -- especially considering the detention center will not close this year either, and the White House can't say when it will.

"I don't know when the process will be done," White House Press Secretary Robert Gibbs said Thursday.

Wanting to close Guantanamo Bay was hardly a novel idea when Obama took office. President George W. Bush wanted to close the prison camp as well, but couldn't come up with a date or a plan. Obama's date is gone, and he's still working on a plan.

"One question that that raises, of course, is whether the Obama administration is drifting toward a policy very similar to the one that the last president articulated with respect to Guantanamo," said Benjamin Wittes, with the Brookings Institution.

So what happened? How could a president so emphatic then be so incapable of following through now?

"One, naivete. And two, irrational exuberance that they were going to be better, stronger and faster," answered Charles Stimson, a legal fellow with the conservative Heritage Foundation.

Wittes said the administration "genuinely underestimated" the difficulty of carrying out the plan.

So far, 44 detainees have been released from Guantanamo Bay under the Obama administration.

There are 196 still in custody, about 50 of which are being held indefinitely without trial. Thirty-five are heading to U.S. trials and 110 will be transferred to other countries.

Stimson, a former Bush adviser, credits the Obama team for at least deciding the fate of each detainee.

"You do need to rack and stack them, and first you need to put your arms around all the information about each detainee. We didn't do that in the Bush administration as well as they have," he said.

But Obama's decision to keep some detainees without trial contradicts his pledge in May to work with Congress on a new indefinite detention law. That reversal puts him right where Bush was -- asserting that war powers in Afghanistan allow for indefinite detention of terror suspects.

"The administration changed its mind and decided that they're not going to do it because it's too politically difficult I think they deserve a lot of criticism for that," Wittes said.

Those detainees are heading to the maximum security prison in Thomson, Ill., a facility that won't be ready for months, if not a year. Once they arrive, those suspects could come back to haunt the president.

"Judges will order some of those guys into the United States because their rights have not been defined, their privileges have not been defined," Stimson warned.

Fox News' Major Garrett contributed to this report.