The post 9/11 world was just a few days old when was first imprisoned. Captured by Afghan bounty hunters while attempting to flee from Kabul with his pregnant wife and their three children, he was sold on twice, and found himself in US hands.
By the end of the year he was being held at the notorious interrogation centre that American forces and the CIA had established at the Soviet-era airfield at Bagram, north of the capital.
Whatever happened there may explain why Aamer has languished for so long at Guantánamo, remaining behind bars long after every other British national and resident had been set free.
The interrogators that MI6 and MI5 had sent to Bagram were warned that they must not take part in the torture that was being inflicted on the inmates; all received written instructions that “we cannot be party to such ill treatment nor can we be seen to condone it”. In practice, this meant that they would remove themselves from the room before the abuses began.
After being transferred to Guantánamo, Aamer gave a statement to his lawyers in which he alleged that, despite these instructions, British intelligence officers were present while he was being severely beaten at Bagram. As a consequence of this – and because of the UK’s wider involvement in his unlawful detention and mistreatment – he is expected to embark upon legal proceedings against the British government once he returns to the UK.
Furthermore, Scotland Yard detectives investigating the British government’s involvement in rendition after 9/11 are understood to have taken a from him at Guantánamo.
Members of his legal team suspect that the UK’s intelligence agencies have been so alarmed by the prospect of such allegations being aired on his return to the UK that they may have fed false information about Aamer to the US authorities in order to impede that release.
At Guantanamo, the prison authorities came to the that Aamer had once been close to Osama bin Laden. He denies any terrorist connections. He has faced no charges, and has twice been cleared for release to Saudi Arabia, the country where he was born. He and his lawyers have insisted that he should be permitted to return to the UK, to be reunited with his British wife and his four British children.
For several years, both William Hague, as foreign secretary, and David Cameron have been appealing publicly to Barack Obama to set Aamer free, but successive US defence secretaries have refused to sanction his release.
Senior Whitehall sources have told the Guardian that both Hague and Cameron were genuinely committed to doing everything they could to secure the release of Aamer. While Theresa May is said to have been less enthusiastic to see Aamer living in the UK, officials say there is no evidence of any back-channel messages being passed from the Home Office that would explain Aamer’s continuing detention.
According to these sources, the same cannot be said of MI6, with one saying that there is a suspicion that some intelligence officers may have been dripping poisonous messages about Aamer into American ears at the same time that the prime minister and foreign secretary were attempting to secure his release. There are some “who still consider themselves to be above the law”, the source said.
Aamer is now 48. He is said to have suffered lengthy bouts of depression during years of imprisonment, as well as post-traumatic , but also to have been defiant and uncooperative for long periods.
The campaign to secure his release eventually attracted support from many thousands of members of the public, as well as figures from popular culture, the arts and politics. News of his impending release will be celebrated by Jeremy Corbyn and Paul Dacre, editor of the Daily Mail, both of whom for his release.
Aamer’s eldest child, Johina, is aged 17, while his youngest, Faris, aged 13, has never seen him. On Friday, Johina thanked her father’s supporters via Twitter, and said: “The news hasn’t hit yet. We can’t believe we might finally see our Dad after 14 years.”