John:

Thank you for that. Those mandates you quote simply describe the overarching authority of a commander-in-chief rather than the ethics and moral guidelines for exercising that authority.

really leaves the door open, what?

If that is the extent of the ethical compass and restraints, we don't have any reason to damn any Napoleonic commander for his actions unless he went beyond the 'restraints' of his 'supreme executive chief'. In Napoleon's position, he was that supreme executive, so was ethically allowed to do just about anything in a time of war. Wellington too was hardly restrained 'within the limits of his military jurisdiction.'

Bill

Up to a point Bill, you might be right. Given that this is the first time I have considered the question in specific terms, I am unable at this point to offer any more intelligent commentary. In the chapter of Glenn's book in the link he expands on the topic, and does make reference to moral precepts such as decency and restraint; you could say, the moral obligations of the upper echelons of society post-Enlightenment; ideally speaking.

Obviously thinking on the subject will have developed in the subsequent hundred years, but Glenn writing in in 1918 was also hundred years closer to the era of Napoleon and Wellington, even if he was writing in the dawn of the age of Total War.