Donald Trump, Barack Obama differ on plans for Guantanamo Bay, Cuba

The entrance to Camp VI detention facility guarded at Guantanamo Bay Naval Base, Cuba. Photo / AP

For eight long years, Barack Obama did everything he could to close America's most controversial prison.

He whittled down the number of detainees from well over 200 to less than half of that. He spoke publicly about the damage the facility was doing to America's reputation, and the danger its continued operation posed as a recruiting tool for the world's worst terrorist organisations.

On his first day as president in January 2009 he signed an executive order to close Guantanamo Bay and transfer detainees - including a number of convicted terrorists - to other countries.

But it appears to have been for nothing. On Monday, he lamented his administration's inability to "close the darn thing", citing congressional restrictions.

Enter President-elect Donald Trump, who it appears has a completely different idea about what to do with the American-run prison at the southern end of Cuba.

Obama has two months left in the oval office to do the almost-impossible. Advocates for the closure of the facility say their fears grow every day that a Trump-run Gitmo could become a reality. It's not a promising scenario.In April, he made his intentions crystal clear: "We're gonna load it up with some bad dudes, believe me," he told the Miami Herald. "We're gonna load it up."

'THIS ISN'T 2003'

President Barack Obama meeting with President-elect Donald Trump. Photo / APObama was visibly disappointed this week as he stood behind the podium to update the American public on the prison he's struggled with since taking office.

"With respect to Guantanamo, it is true that I have not been able to close the darn thing," he told reporters.

"What is true is that we have greatly reduced the population. You now have significantly less than 100 people there. There are some additional transfers that may be taking place over the next two months.

"There is a group of very dangerous people that we have strong evidence of having been guilty of (committing) terrorist acts against the United States, but because of the nature of the evidence - in some cases that evidence being compromised - it's very difficult to put them before a typical Article III court."

The numbers are down, but Robert Chesney, a professor at the University of Texas School of Law in Austin, says Trump will likely ramp those numbers right back up.

"We might end up with more detainees there," he told AP. "(But) this isn't 2003, with relatively large numbers of terrorism suspects in places where we have a realistic opportunity to nab them."

He said detainees could include Islamic State fighters captured in Iraq or Syria.

The prospect is a frightening one for advocates. Naureen Shan, director of security and human rights at Amnesty International, said Obama knows what's on the line.

"He knows what's at stake and he knows he can't leave the door to Guantanamo open for Donald Trump," she said.

'MOST TORTURED' PRISONER SPEAKS

The negative press levelled against Gitmo continues despite steps in the right direction. In October, Mohamedou Ould Slahi walked free preparing to tell all about life inside the detention centre.

The Mauritian national wrote the best-selling Guantanamo Bay Diaries, published in January last year. He said very little after being let go without charge after 14 years, but could blow the lid on life under American military rule.

In one passage from his memoir, he detailed how he was sexually abused by female interrogators and, at one point, driven out to sea and forced to drink salt water until he vomited.

He had originally been arrested by US forces after 9/11. He was accused of fighting with al-Qaeda, but it was never proven.

Last month, former staff at the centre spoke out about the long-lasting impacts of their job. An Army Institute of Public health study, obtained by VICE News, revealed how hundreds of former troops showed signs of post traumatic stress disorder or developed behavioural health conditions.

It's another reason for Obama to close it down, but it's not that simple.

He's tried time and time again.

In May 2014, the Senate voted overwhelmingly against Obama's proposal to close Guantanamo using taxpayer funds. They later voted against transferring detainees into the United States on security grounds.

His own vice president, Dick Cheney, undermined him.

"I think the President will find, upon reflection, that to bring the worst of the worst terrorists inside the United States would be cause for great danger and regret in the years to come," Cheney said.

CNN reported that 48 detainees were transferred from Cuba to outside countries in 2009, and that number dropped to 17 the following year and zero the year after.

Transfers increased in 2014 but there are still almost 100 detainees behind bars in Cuba today. A number far too high for the outgoing president.

WHAT NOW?

President-elect Donald Trump and his wife Melania walk with Senate Majority Leader Mitch McConnell on Capitol Hill. Photo / AP

Congress has blocked the closure because agreement has yet to be reached on where to move those still behind bars.

There are 60 remaining prisoners there, according to AP, and of those, an interagency security review has cleared 20.

An administration official, who spoke on condition of anonymity, said officials expect to complete a "substantial number" of those transfers before Trump takes over on January 20, 2017.

Senator Pat Roberts, a Republican who opposes moving inmates, said last week the Defense Department told him months ago that "the Obama administration had neither the time nor the money to close Gitmo and move detainees," AP reported.

Trump has not addressed the Guantanamo plan since winning the election, but his track record speaks volumes.

The full "load it up" quote is illuminating.

"This morning, I watched President Obama talking about Gitmo, right, Guantanamo Bay, which by the way, which by the way, we are keeping open," he told reporters.

"Which we are keeping open ... and we're gonna load it up with some bad dudes, believe me, we're gonna load it up."

Lawfare, a national security blog, posed an important question. Editor-in-chief Ben Wittes wrote: "With whom? ... Trump's stated military strategy and ambition are so hard to figure out that it's not all clear to me what the captive population that would be subject to being moved to Guantanamo is, who they would be or where they would come from."

For now, Trump remains quiet about his ambitions. One thing is certain - that won't last.