This is treated as customary international law, based on a UN Security Council conclusion in 1993 making it binding also for non-signatories.
https://en.wikipedia.org/wiki/Fourth_Geneva_Convention
For instance, break it anywhere in the world by killing civilians, and enter my country (say, as a refugee), and you'll be prosecuted if caught. There's even a recent example (a man got life sentence for what he did in Rwandan conflict; the life sentence here is practically something like 12 years).
I'm still not clear that this applies since our enemies do not meet the requirements outlined beyond being signatories (what with insignia and organized ranks etc). Article 3 also refers to conflicts not of an international nature. I'm not sure how that's interpreted. Is that civil wars? Or just wars involving non-state actors? The "war on terror" certainly has an international character.
[...]
Unlawful combatants don't have access to the rights under war laws, except Article 3 of the Geneva Conventions (see quote below).
Hence, the question is not if you treat them as POWs or as civilians -- but if they have the protection of a POW at all.
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[This was my reference for the previous claims. The Wikipedia link go to the Convention. I earlier referenced the relevant US law and their Supreme Court, which also discuss this.]
https://en.wikipedia.org/wiki/Unlawful_combatant
The Geneva Conventions do not recognize any lawful status for combatants in conflicts not involving two or more nation states. A state in such a conflict is legally bound only to observe Article 3 of the Geneva Conventions and may ignore all the other Articles. But each one of them is completely free to apply all or part of the remaining Articles of the Convention.[6]
First, no. You asserted it repeatedly without a compelling reference. Ptaipale provided a verifiable claim about the UN Security Council affirming that this had become international law. You linked to an article that happened to make a similar claim but had no reference to the UN Security Council decision (nor does the citation it references so far as I can see).
Second, I admitted a gap in my knowledge and your response was to come in and assert that you told me the same earlier (which you actually didn't). If the point of your arguing was to educate, this is a really poor technique. Don't respond to someone acknowledging a mistake/misunderstanding/knowlege gap by trying to make it about how "right" you are. It comes off as petty.
My personal heuristic to avoid grief in the future: Don't discuss with anyone that dismiss Wikipedia without references... no, without having primary sources for references.
Thank you for that. The net and HN will be better for me.
(Edit: The UN and the UN Security council make resolutions all the time. I doubt a majority are followed. :-) E.g. http://articles.latimes.com/2002/oct/17/world/fg-resolution1... )
I'm glad I could help.
https://ihl-databases.icrc.org/applic/ihl/ihl.nsf/ART/375-59...
In addition to the provisions which shall be implemented in peace time, the present Convention shall apply to all cases of declared war or of any other armed conflict which may arise between two or more of the High Contracting Parties, even if the state of war is not recognized by one of them.
The Convention shall also apply to all cases of partial or total occupation of the territory of a High Contracting Party, even if the said occupation meets with no armed resistance. Although one of the Powers in conflict may not be a party to the present Convention, the Powers who are parties thereto shall remain bound by it in their mutual relations. They shall furthermore be bound by the Convention in relation to the said Power, if the latter accepts and applies the provisions thereof.
By my reading, this applies to conflicts between signatories or conflicts involving a signatory and a non-signatory who accepts the terms of the convention. So not strictly nation states, but also not every party to every conflict.