WASHINGTON (AP) - President Barack Obama is staunchly defending his decision to close the Guantanamo prison facility, calling it "a mess," and saying he won't do anything to endanger the American people.

In fact, Obama said the very existence of the Cuban prison facility compromised U.S. national security and served as a recruiting point for the al-Qaida network.

He argued in a speech Thursday that roughly 500 detainees already had been released by the Bush administration and said operating the Guantanamo facility "set back the moral authority that is America's strongest currency in the world." The president spoke to an audience of military lawyers in a cavernous hall of the National Archives, standing before a display of the Constitution, Bill of Rights and Declaration of Independence.

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WASHINGTON (AP) - President Barack Obama finds himself in a political box - at home and abroad - on closing the Guantanamo Bay prison, and will be trying Thursday to use a major address on national security to work out of the tight spot.

Obama takes on the explosive topic a day after the Senate, at the behest of majority Democrats, denied his request for $80 million to close the prison. The 90-6 vote followed a similar move last week in the House and underscored widespread apprehension among Obama's Democratic allies in Congress over the issue.

In an e-mail summarizing topics the president will address, a senior administration official did not mention the congressional setback. Instead, the official said. the Obama administration was working through what he termed a "flood of legal challenges" that are left over from the Bush administration's handling of Guantanamo prisoners.

Providing a summary of the speech on condition of anonymity because it has not yet been delivered, this official wrote that the president will work through the cases of the remaining 240 prisoners at Guantanamo by:

-Using federal courts to try those who have violated criminal law;

-Using military commissions to try those charged with violating the rules of war; and

-Transfering detainees to third countries when that is possible and does not pose a security risk.

In spite of lawmakers' concerns, the administration plans to send a top al-Qaida suspect held at Guantanamo Bay to New York to stand trial for the deadly 1998 bombings of U.S. embassies in Africa, Attorney General Eric Holder announced early Thursday. The suspect, Ahmed Ghailani, would be the first Guantanamo detainee brought to the U.S. and the first to face trial in a civilian criminal court.

On his second day in office, Obama announced that within one year he would close the prison that was constructed by the Bush administration at the U.S. naval base in Cuba to hold terrorism suspects, most of them captured in Afghanistan.

The Obama administration says the lockup had become a "recruiting poster" for al-Qaida because prisoners were being held indefinitely without charges and some were subjected to "enhanced interrogation," including waterboarding - a simulated drowning technique that Obama has called torture.

But when prisons close, inmates must either be released or sent to other jails, and Obama still "has not decided where some of the detainees will be transferred," spokesman Robert Gibbs said Wednesday.

That's the nub of Obama's problem with both U.S. politicians and America's allies abroad, who have been asked by the administration to accept some of the prisoners.

With Wednesday's action in the Senate, lawmakers from both houses of Congress have gone on record criticizing the lack of specific plans about where to house inmates who are considered too dangerous for release or transfer to other countries.

Some Republicans also cite what amount to ideological concerns, viewing the closure as a security misstep and a further repudiation of former President George W. Bush. And both Democrats and Republicans have been retreating from an uproar in their districts over the possibility that terror suspects would be housed in local prisons.

That's a fairly empty sales pitch for administration officials who are trying to persuade European and Muslim allies to take some of the detainees.

And they got no help Wednesday when FBI Director Robert Mueller told Congress that bringing Guantanamo detainees to the United States could pose a number of risks, even if they were kept in maximum-security prisons.

Gibbs and Attorney General Eric Holder both quickly responded that Obama would never do anything to endanger Americans.

Obama has named senior diplomat Daniel Fried as special envoy on the issue. So far he's had little success in garnering commitments abroad and his task only grows more onerous with the votes in Congress to deny money to close the prison.

While France has accepted one prisoner, fulfilling a promise made when Obama attended a NATO summit in April, other European allies have refused or given nonspecific commitments.

As the debate on Guantanamo built in advance of Obama's speech Thursday, Gibbs said the president understood such concerns and hoped to ease worries about prisoner resettlement.

Former Vice President Dick Cheney, who was deeply involved in the Bush administration's development of Guantanamo policy, also was speaking Thursday on the topic at the conservative American Enterprise Institute. Cheney has been an outspoken critic of Obama and his plans for closing the prison, saying they would make Americans less safe.

In addition to Guantanamo plans, Obama's speech at the National Archives was expected to touch on his recent decisions to withhold pictures of enhanced interrogations, the decision to continue using military commissions to try some terror suspects and other legal issues surrounding the handling of the prisoners.

Obama also has been forced to fight a rearguard defense on his larger plans for handling terror detainees. Organizations like the American Civil Liberties Union have become noisy critics of the administration as the president has backed away from expunging military tribunals from the tool kit for handling prisoners.

Concerns on that front were sufficient Wednesday that Obama met at the White House with ACLU Executive Director Anthony D. Romero and representatives of the Center for Constitutional Rights, Human Rights Watch and other such organizations.

"I left the meeting feeling discouraged that President Obama plans to continue with many of the same policies of the Bush administration," Romero told The Associated Press.

Romero described the meeting as unprecedented and voiced chagrin that word of it had been leaked to reporters.


Associated Press writers Desmond Butler, Philip Elliott and Devlin Barrett contributed to this report.

Copyright 2009 The Associated Press.