My point is not to defend the French, but to ask if any nation - other than Britain (and perhaps America) - adopted and enforced a code of "civilized" conduct toward civilians based on principles similar to Vattel and Martens.
I know of none. Maybe such exists. And clearly we can look at many social, economic and military features of the British experience as quite unique compared to many other countries, not least of which :
- small and volunteer army
- greater culture of democracy and individual rights and liberties
- more fully developed idea of private property, larger middle class
- essentially unlimited money
- operating usually on friendly territory
- glacial pace of strategic advance (5-6 years to cover Iberia).
In general, I find that any army of the period that campaign on the move in unfriendly territory for more than a couple of weeks with a corps or larger formation seems to have started immediately upon foraging and abuse of the local population. There are many examples, including even a couple of British ones. I think there may have been technical or physical limitations that prevented adequate logistics support of such operations.
If you say that nation states "should not" place their armies in such positions, as atrocities committed on civilians are so likely to begin, then fine. That is a moral judgment and in the light of later history maybe a very reasonable one.
However, then you must say that the Moore should have surrendered, and the Russians should have stopped the pursuit of the French at their border.
You point your criticism only at the French. I do not debate your criticism. Instead, I debate its being pointed uniquely at the French. I have the impression that you have so pointed your criticsm out of malice, and un-informed or ill-informed bias. I have the impression of the avid and even gleeful re-telling of allied propaganda, not scholarship.
If this is the impression that you wish to give, then fine.
On the other hand, if you wish to establish why we should not equally blame all nations (including Britain and Russia per my two examples) who allowed their troops to fight when they could not be supported by "civilized" logistics, I am all ears.