– President Obama on Tuesday recommitted to his years-old vow to close the Guantanamo Bay prison following the arrival of "medical reinforcements" of nearly 40 Navy nurses, corpsmen and specialists amid a mass hunger strike by inmates who have been held for more than 10 years without trial.

"It's not sustainable," Obama said at a White House news conference.

"The notion that we're going to keep 100 individuals in no man's land in perpetuity," he said, makes no sense. "All of us should reflect on why exactly are we doing this. Why are we doing this?"

Citing the expense and the foreign policy costs of continuing to operate the prison, Obama said he would try again to persuade Congress to lift restrictions on transferring inmates to the federal court system. Obama was ambiguous, however, about the most difficult issue raised by the prospect of closing the prison: what to do with detainees who are deemed dangerous but could not be feasibly prosecuted.

Obama's existing policy on that subject, which Congress has blocked, is to move detainees to maximum-security facilities inside the United States and continue holding them without trial as wartime prisoners. It is not clear whether such a change would ease the frustrations fueling the detainees' hunger strike.

Yet at another point in the news conference, Obama appeared to question the policy of indefinite wartime detention at a time when the war in Iraq has ended, the one in Afghanistan is winding down and the original makeup of Al-Qaida has been decimated.

"The idea that we would still maintain forever a group of individuals who have not been tried," he said, "that is contrary to who we are, contrary to our interests, and it needs to stop."

But in the short term, Obama indicated his support for the force-feeding of detainees who refused to eat.

"I don't want these individuals to die," he said.

As of Tuesday, 100 of the 166 prisoners at Guantanamo were officially deemed by the military to be participating in the hunger strike, with 21 "approved" to be fed the nutritional supplement Ensure through tubes inserted through their noses.

In a statement released earlier, a military spokesman said the deployment of additional medical personnel had been planned several weeks ago as more detainees joined the strike.

"We will not allow a detainee to starve themselves to death, and we will continue to treat each person humanely," said Lt. Col. Samuel House, the prison spokesman.

Ethical issues

The military's response to the hunger strike has revived complaints by medical ethics groups that contend that doctors — and nurses under their direction — should not force-feed prisoners who are mentally competent to decide not to eat.

Last week, the president of the American Medical Association (AMA), Dr. Jeremy A. Lazarus, wrote to Defense Secretary Chuck Hagel saying that any doctor who participated in forcing a prisoner to eat against his will was violating "core ethical values of the medical profession."

"Every competent patient has the right to refuse medical intervention, including life-sustaining interventions," Lazarus wrote.

He also noted that the AMA endorses the World Medical Association's Tokyo Declaration, a 1975 statement forbidding doctors to use their medical knowledge to facilitate torture.

It says that if a prisoner makes "an unimpaired and rational judgment" to refuse nourishment, "he or she shall not be fed artificially."

The military's policy, however, is that it can and should preserve the life of a detainee by forcing him to eat if necessary.

Protest escalated

The current protest began in February and escalated after a raid this month in which guards confined protesting detainees to their cells.

The impetus for it is disputed, but both sides agree that the root cause is frustration over the collapse of Obama's effort to close the prison, which drew congressional resistance, and the fact that no prisoners have been transferred because of restrictions on where they can be sent.