Earlier quoted context omitted.
So either they're civilians that have been arrested for crimes or they're prisoners of war. You have to choose and then play by those rules. Inventing new terms ("enemy combatants") isn't going to convince anybody but the most gullible. The term is "unlawful combatant" and has the meaning of someone on the battlefield out of uniform. In the case of spies, they can be summarily executed perfectly legally - i.e. withou…
Certainly the Geneva Convention doesn't have legal force in this case, but I like to think that one can aspire to high standards of behaviour without the threat of legal sanction. In other words, do we obey Geneva Convention rules because we're forced to, or because it's right?
But in response to "there are pretty strict guidelines on the treatment of prisoners of war" - those guidelines, by their own definition, carry no legal weight in this context. Since the Taliban fighters are not uniformed members of the Army of a Geneva Convention signatory, they aren't actually "prisoners of war" for a start...