There is another solution
The US government should consider simply extraditing him to Afghanistan to stand trial and be punished in accordance with their standards, for crimes committed against the Afghan people when he was on their soil. By being a foreigner and joining and taking up arms for the Taliban, Johnie is no doubt a criminal in the eyes of the Afghans.
I see no special reason to shield him from such a fate just because he's an American citizen, and I certainly wouldn't care if the new Afghan government threw this little rat boy into a hole in the ground for the next 10 years or so.