May I respectfully ask a couple of questions about your example?
First, I assume that you assume (are we on dangerous ground or what?) that the juridical situation is one of an invading / occupying army in a foreign nation whose government has either not surrendered or is not existent. Correct?
Next a hypothetical, if the names and places were changed to reflect an army of the established government in a province for the purpose of suppessing an open rebellion, would these orders take on a different juridical characteristic?
Then, when did the Law of Nations start applying to the internal affairs of nation states?
I did not ask about the laws of humanity or the "natural" law. Voltaire may have had something to say about the "natural" law; I'm not sure.
Thanks, BaldJim