President Obama sent his plan to close the Guantanamo prison to Capitol Hill, where it was met with immediate condemnation. (Jason Aldag,Julie Vitkovskaya/The Washington Post)

President Obama urged lawmakers on Tuesday to help him close the military prison at Guantanamo Bay, Cuba, making his case for a White House plan to shutter a detention facility he said symbolizes excesses that followed the Sept. 11, 2001, attacks.

“This is about closing a chapter in our history,” said Obama, flanked by Vice President Biden and Defense Secretary Ashton B. Carter, in remarks at the White House. “It reflects the lessons that we’ve learned since 9/11, lessons that need to guide our nation going forward.”

Obama’s blueprint, which added some detail to earlier White House plans to move as many as 60 prisoners to the United States for trial or continued detention, was met with immediate condemnation from Capitol Hill.

Sen. John McCain (R-Ariz.), one of the few senior Republicans who has expressed openness to closing the detention center, said the nine-page plan failed to address basic questions. In a statement, McCain said Obama had “missed a major chance” to build support for closing the prison before he steps down in January.

“What we received today is a vague menu of options, not a credible plan for closing Guantanamo, let alone a coherent policy to deal with future terrorist detainees,” he said.

The instant rejection makes it unlikely the plan will advance in the Republican-controlled Congress, meaning Obama must use executive action and further incense his opponents if he intends to achieve one of his core national security goals.

At the heart of the debate is whether the U.S. government can securely house or try on American soil any of the 91 prisoners remaining at the prison.

Whether Obama can make good on his long-standing promise to close Guantanamo will also shape his legacy and provide an important measure of how far he was able to go in distinguishing his presidency from that of George W. Bush, who opened the prison in 2002 and filled it with nearly 800 suspected militants.

Obama argued Tuesday that Guantanamo remains a rallying call for terrorists.

“I don’t want to pass this problem on to the next president, whoever it is,” Obama said. “If, as a nation, we don’t deal with this now, when will we deal with it?”

To allow the closure plan to move forward, lawmakers would have to alter current laws that prohibit the administration from spending any money on bringing detainees to the United States or even making plans for doing so.

Since he took office in 2009, Obama has resettled overseas 147 Guantanamo prisoners who were deemed to pose a minimal security risk. Of the 91 remaining at the prison, 35 have been cleared for transfer to other nations. Ten more are in some stage of a slow-moving military trial process.

Previewing the closure blueprint Tuesday morning, senior Obama aides said that 30 to 60 detainees are expected to be brought to U.S. facilities if the plan is approved. In the document, the administration said it had reviewed 13 potential facilities in the United States that might be used to house detainees, but it did not name them.

If brought to the United States, some of those detainees would continue through military commissions; others might face trial in civilian courts. Early in the Obama administration, officials planned to bring a number of Guantanamo prisoners to stand trial in federal court but backed down amid political objections.

In instances where prosecutors lack evidence or see potential evidence as problematic, other detainees, deemed too dangerous to release, would probably be detained indefinitely without trial.

Laura Pitter, senior national security counsel at Human Rights Watch, said Guantanamo has been a “blight” on the United States’ reputation worldwide. “It is well beyond time to shut it down,” she said in a statement. “But transferring some detainees to the U.S. for continued detention is not a solution. Most detainees at Guantanamo have been held there for nearly 14 years without charge or trial in clear violation of international law.”

White House officials have also tried to make a fiscal case for closing the prison.

According to the plan, it would cost between $290 million and $475 million to prepare a facility in the United States and transfer detainees there. But officials estimated that within three to five years, the lower annual costs of a U.S. facility with fewer detainees would “generate at least $335 million in net savings over 10 years and up to $1.7 billion in net savings over 20 years.”

It costs almost $450 million a year to operate the prison at Guantanamo.

Officials conceded that their budgetary estimates were rough, saying the lack of precision was a result of the congressional prohibition on planning for the prison’s closure.

The Obama administration must also grapple with objections from critics who argue that Guantanamo detainees are too dangerous to release.

According to the Office of the Director of National Intelligence, six detainees released since Obama took office were confirmed as of July to have returned to militant activity.

Each suspected case has made the White House’s argument harder to make. On Tuesday, Spanish authorities said they had arrested a former Guantanamo inmate who they believe was involved in recruiting fighters for the Islamic State.

“President Obama’s determination to move some of the world’s most dangerous terrorists to U.S. soil is inexplicable and unacceptable,” Rep. Devin Nunes (R-Calif.), chairman of the House Intelligence Committee, said in a statement.

Obama declined to address whether he will try to close the prison even if Congress opposes his plan. For months, the president’s top advisers have hinted that the White House may try to take executive action on Guantanamo, essentially going around Congress.

While military leaders have signaled that they do not currently believe they have the authority to take steps to close the prison, the White House or the Justice Department could issue a new interpretation of existing law and instruct the Pentagon to do so.

A former senior administration official, who spoke on the condition of anonymity to discuss administration deliberations, said that ordering officials to defy Congress would require “the mother of all [Justice Department] opinions.”

The blueprint did receive support from some lawmakers, including Sen. Jack Reed (D-R.I.), who urged fellow lawmakers to consider it.

“Let’s be clear,” Reed said in a statement. “Closing GITMO does not mean releasing anyone, setting bad guys free, or doing anything other than putting them in a highly secure prison and on trial under the right military tribunal system or legal process.”

Obama’s announcement immediately became fodder for the presidential campaign trail. On Tuesday, Sen. Ted Cruz (R-Tex.) called for expanding Guantanamo, not closing it.

Speaking at a rally in Nevada, Sen. Marco Rubio (R-Fla.) promised that, if he is elected, future captured militants will not be granted a federal court hearing. “They are going to Guantanamo, and we are going to find out everything they know,” he said.

Republican presidential candidates have already promised that if elected, they would overturn any executive action Obama has taken.

Ellen Nakashima contributed to this report.

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