Straining to make out the Arabic translation of the proceedings through his headphones, Nashwan al-Tamir zoned in and out listlessly. The pre-trial hearing must have had a Groundhog Day feel for the 60-year-old Guantanamo Bay detainee, who has grown old waiting for the chance to plead his innocence.

It has been 14 years since Mr Tamir – accused of being one of the late al-Qaeda leader Osama bin Laden’s deputies – was brought to the US military base and more than seven since he was arraigned on war crimes charges.

The Iraqi stroked his beard, which has grown long and white during captivity, as he watched the fourth judge introduce himself to Courtroom Two at “Camp Justice”.

US President Joe Biden made a promise to fulfill his predecessor Barack Obama’s pledge to close the Cuban detention facility, but six months into his administration there are doubts over whether he is willing, or even able, to.

As the US extricates itself from its longest-ever war in Afghanistan, the military commission trials at Guantanamo drag on interminably.

Reporters were given access to the prison camp, the paper’s first visit in nearly a decade. With the release of a Moroccan national last week, there are now 39 prisoners remaining at “Gitmo”. Eleven have been charged, five in relation to the 9/11 attacks. Ten more were cleared for release years ago but continue to be held without charge. The rest exist in limbo.

Mr Tamir, a former Saddam Hussein Iraq Army major arrived at Guantanamo Bay from one of the CIA’s secret black sites, where detainees were subject to what the agency called “enhanced interrogation techniques”.

Mr Tamir, charged under the name Abd al-Hadi al-Iraqi, has already been through three judges and 20 defence lawyers. The first two justices were reassigned, while the third recused himself over a conflict of interest.

Reporters sat in on a “voir dire” hearing, to determine a judge’s fitness to preside over a case. Mr Tamir’s defence team cross-examined Lt Col Michael Zimmerman as they tried to identify any potential issues that could cause further delay.

“The fact that my client’s trial has been going on for seven years and yet today we’re discussing how to start over from the very beginning, again, is evidence that it doesn’t work,” said Susan Hensler, Mr Tamir’s defence lawyer.

“The military commissions have been a complete failure.”

Estimates suggest each prisoner costs the US somewhere in the range of $13m (€11m) a year. That does not include money spent on the trials. The entire courtroom, from the prosecution and defence teams to the judge and translators, is essentially airlifted from Joint Base Andrews outside Washington DC to the southeastern tip of Cuba.

One interpreter said he has made the journey 420 times since 2002.

A frail Mr Tamir in a blue dishdasha and taqiyah, or skullcap, shuffled around the room on a walker as masked and gloved prison guards looked on.

It is not clear what evidence the US government has against Mr Tamir as it is yet to be presented. Some of it is thought to be testimony he gave under torture while at the CIA black site. Much of it is classified, meaning even his lawyers are unable to access it to mount their client’s defence.

To date, only eight of Guantanamo’s some 780 detainees have been convicted in the military commissions after trial or plea bargain. However, three of these convictions were overturned and three more were partially invalidated.

Images of the first prisoners at Guantanamo kneeling in orange jumpsuits with their hands tied behind their backs shocked the world when they were released in 2002.

The first batch was brought to temporary holding facility Camp X-Ray. Overgrown weeds and vegetation now cover the kennel-like metal cages. The wooden watchtowers have started to crumble, worn down by the hot Caribbean sun.

Today, naval families occupy houses that overlook the site – a sign of how normalised the detention centres have become among those who live and serve on the base, which was opened in 1898 in agreement with the Cuban government.

“The exposure it received as a result of the detention centre is understandable, but it’s not the sole function of this installation,” Capt Samuel White, the base’s chief, said when asked about how its dual missions co-exist.

“I’m not making a judgement – good, bad, whatever – on whether something needs to be put behind us.”

American sentiment on Guantanamo has changed greatly over the years. In the aftermath of 9/11, public support was high. However, the pendulum swung as the US became bogged down by the intractable conflicts in Iraq and Afghanistan.

Now, as the US winds down its involvement in both wars, it is left with the quandary of what to do with their prisoners.

Traditionally, when conflicts end, wartime detainees are sent home. But the government has taken the position that the war on terror Congress authorised is bigger than the conflict in Afghanistan.

Lawyers for the detainees are trying to argue through US federal court that whatever legal authority the government had to detain their clients is about to timeout.

“The case is essentially a litigation of the war on Afghanistan, and the war is over. President Biden told us that last week,” Mrs Hensler said.

“The United States entered into a peace agreement with the Taliban a year and a half ago and here we still are.

“My client is a prisoner of war, he should be sent home.”

John Kirby, Pentagon spokesman, said there was no direct link between its future and the coming end to the “mission” in Afghanistan.

Joseph Marguiles, one of the first Gitmo defence lawyers and author of Guantanamo and the Abuse of Presidential Power, said it is unlikely Mr Biden will make any sudden announcement.

“The Biden administration learned from the mistake of the Obama one, which was to make its closure into a big political deal,” Mr Marguiles, an attorney with the MacArthur Justice Center, said.

“Obama was told to just quietly release a guy every few months, gradually bringing the number down as low as he could. That’s just what Biden is going to do over the next four years.”

Telegraph Media Group Limited [2021]