Specifically, which Geneva Convention states that? The Convention linked to in a previous post simply defines 'Prisoner of war', and the protections of those prisoners.
I have yet to find any Geneva Convention which even uses the term 'lawful combatant'.
The point is that to be covered by Geneva Conventions you must behave in certain ways. The insurgents (which some want to classify as militias) do not meet the criteria, and thus, are NOT covered under the Geneva Convention, although, as with the case of Gitmo, they are being treated as if they do.
Generally speaking, some call those who abide by Geneva to be legitimate or lawful, whereas those who do not are outside the convention, are illegitimate or in other words, outlaws. Lawful combatants and unlawful combatants. Use whatever terms you like to identify the innies verses outies- what you cannot do is treat the GC as if it protects all combatants equally. It doesn't. To do so would defeat its entire purpose- which is to minimize damage to civilians. That's what all those POW passages are about- not about protecting soldiers but rather, protecting civilians from being taken as hostages, used as shields, cremated in ovens, etc- by making it worthwhile for a soldier to risk being killed in the open battlefield rather than shield himself by hiding behind some noncombatant or in some hospital in town. A soldier doesn't want to risk his POW status if captured and be treated as an outlaw, so he will behave in more desirable and disciplined ways. If we treat terrorists to POW status, on the other hand, then our enemies would have every reason to behave like terrorists instead of like soldiers.
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