What a stupid argument

Reuters - A military Defence lawyer said Omar Khadr, who was captured in a firefight in Afghanistan at age 15, had abandoned the jihadist teachings of his al Qaeda financier father, apologized to his victims and accepted responsibility for his actions.

He called Khadr "a child with a bad dad" and urged the military jurors to free him and give him a chance to go to school and become a contributing member of society.

"This case is about giving Omar Khadr a first chance because he's never had it," Lieutenant Colonel Jon Jackson told the jury. "There's going to be no good keeping him here."
...
He dismissed a prosecution psychiatrist's testimony that Khadr was too dangerous for release, in part because he had been "marinated in jihad" during the years he was locked up with radical adult prisoners at Guantanamo.

That was the U.S. government's fault, said Jackson. He portrayed Khadr as a rule-abiding prisoner and eager student who deserved a chance at rehabilitation and had come to realise that "hate solves nothing."

Emphasis mine.
You put him a jail with radical adult prisoners, force him to be marinated in jihad, and then use that as an argument to lock him up longer?