Back in 2002, when America was flying terror suspects out of Afghanistan to its new prison in Guantanamo Bay, the Pentagon was in no doubt that it was incarcerating the "worst of the worst", in the words of one spokesman.
By Patrick Jackson
BBC News Online
"They are bad guys and... if let out on the street, they will go back to the proclivity of trying to kill Americans and others," said Rear Adm John D Stufflebeem.
Hamed Abderrahman Ahmed is facing charges back in Spain
In the years since the prison was created, at least 188 "bad guys" of various nationalities have been repatriated from their sun-baked cells in Cuba.
A Pentagon spokesman told BBC News Online that at least five of those released had "rejoined the fight".
Abdul Ghaffar, a Taleban militant killed fighting in Afghanistan in late September, is known to have spent about eight months in the camp before his release.
But what of all the others, going back to home communities as far afield as Sudan and the UK?
Were at least some of the "worst" not so bad after all?
No case to answer
For Amnesty International, the stream of transfers reinforces its argument that detention without trial as part of an open-ended "war on terror" is unjustified.
"The number of people who have been released and who have not then been charged in their home countries basically underscores the fact that they should never have been in Guantanamo Bay in the first place," a spokesperson told BBC News Online.
The organisation highlights the fact that few Guantanamo detainees "transferred for continued detention" in their home countries face prosecution on their return:
- Seven Russians were released without trial at the end of June, four months after their transfer
It has been unclear what, if any, legal action was taken against four Saudis after their transfer in May 2003
Spain freed Hamed Abderrahman Ahmed on bail on 13 July after holding him four and a half months on suspicion of belonging to a terrorist organisation. It granted bail in view of his experiences in Guantanamo
As of late September 2004, the French authorities
were still holding four men on suspicion of terrorist links after their much-publicised return from Guantanamo in July.
In March, five of nine Britons held at Guantanamo were flown back to the UK and the authorities released them without charge the following day.
Perhaps one of the best-known Guantanamo ex-inmates is Danish national Slimane Hadj Abderrahmane, who announced in September he planned to travel to Chechnya and fight Russian forces.
The 31-year-old went on TV to say his transfer deal with the US authorities not to take part in terrorist activity could be treated as "toilet paper".
The Danish Intelligence Security Service later announced that Mr Abderrahmane had retracted his statement and would stay at home.
For the Pentagon, the transfer of inmates is not an admission that the US got the wrong men - just part of the military screening process in a time of war.
Each detainee who leaves the prison is transferred either for release or continued detention abroad after a careful assessment, said spokesman Maj Michael Shavers.
The US says its treatment of inmates is justified
"Each case is a little bit different", he told BBC News Online, and he cited factors which may lead to a transfer:
- The detainee may have "renounced their fight against the US" and is no longer a threat
The detainee may no longer "contain intelligence value"
It is established that the detainee has not committed any crimes triable by military commission, ie war crimes
In the eyes of the US military, there can be no question of ex-detainees suing the US military for unjustified imprisonment.
"When you capture individuals in a combat situation, you have the right to hold them until the end of hostilities," Maj Shavers said.
He made clear he was referring to the "war on terror" in general, and not the war in Afghanistan specifically.
"This is a precedent used by many countries, in many conflicts, over history," he added.
In July, the authorities at Guantanamo began reviewing individual cases among the remaining detainees, thought to number about 540 as of early October.
Concern has been raised by human rights groups that some of these, such as ethnic Uighurs from China, would face persecution if sent back to their home countries.
With perhaps a few exceptions - such as Afghan teenager Naqibullah who told the BBC that US troops had treated him like a guest and given him an education - former prisoners will take away bitter memories of their time at Guantanamo.
"They did everything to us, they tortured our bodies, they tortured our minds, they tortured our ideas and our [Muslim] religion," said one, Afghan ex-detainee Mohammed Khan, on his return to Kabul in March.
While the US denies the use of torture, its right to maintain a "wartime" prison in Cuba looks set to remain a bone of contention with human rights activists.