Imagine, if you will, that the United Nations existed in the 1860s.
Upon receiving news of Sherman’s March to the Sea, it would not be farfetched to presume that the leading power of the day, Great Britain, would have assembled a coalition of the willing and, armed with the appropriate UN resolutions, intervened on behalf of the Confederacy*.
By the rules of “humanitarian intervention” under which we apparently operate today, it doesn’t matter whether or not Lincoln had any legitimate interest in keeping the union together** – the actions of his generals would have brought upon the north the wrath of the nations.
* Just like today, the nation leading the coalition would have had its personal reasons for wanting to deal some serious hurt to the offending government. So then, as today, one wonders if the motivation for the intervention would have been completely altruistic.
** I have my own opinions on this, but they are not germane to this post.