I'm beginning to like this topic more and more - as it becomes less and less "legal" in its essence. Its essence consists of history, persons, politics, policies and strategies, centered on the civilian-miltary interface that developed General Orders, No. 100 (aka Lieber Code).

BLUF: This 3.5 min video by John Witt, The Great Forgotten Character of the Civil War, sums up his arguments.

All of Witt's videos (as well as some publications) are linked at Lincoln's Code: Related Audio/Video.

The three best video lectures by John Witt on Lincoln's Code (each is about a hour) are these three: Book Talk with Professor John Fabian Witt: Lincoln's Code: the Laws of War in American History (Yale Law School); Lincoln's Code: The Laws of War in American History (Library of Congress); and Lincoln's Code: The Laws of War in American History (Duke Univ.).

Looking at the civilian-military interface according to Witt, we have three components:

1. The Civilians, who were Lincoln, Stanton and Seward in major roles.

2. The Civilian-Military Interface was Lieber.

Lieber, as a young soldier, was badly wounded in Belgium, chasing after Bonaparte. He left Prussia because of his liberal leanings in the 1820s. Lieber was informed by practitioners, who were also theorists and teachers: Machiavelli (e.g., The Art Of War ; see also The Discourses and The Prince on the same Amazon page), Frederick the Great (e.g., Luvaas, Frederick the Great on the Art of War), Clausewitz (e.g., Howard & Paret trans., On War).

Note that Lieber's ideological trajectory was different from the trajectory that led to the International Humanitarian Law currently accepted in the EU: from Vattel ("Father Namby Pamby" in Lieber's words) through Kant (to sum Lieber's opinions, a "closet pacifist") to the "ICRC Community" (the European Conventions and Red Cross from the last half of the 19th century, the League of Nations, the UN, etc.).

3. The Reviewing Panel. Of these general officers, a majority had legal educations, but they were primarily soldiers and secondarily lawyers. The chief example was Henry Halleck (West Point, 3rd in class; like Sherman, he practiced law as a minor part of his life). Halleck wrote two major treatises:

Elements of military art and science, or, Course of instruction in strategy, fortification, tactics of battles, &c. : embracing the duties of staff, infantry, cavalry, artillery, and engineers : adapted to the use of volunteers and militia (1861; 492pp)

This treatise reflected Halleck's study of Jomini, well before the US publication of The Art Of War (1862 Eng. trans). Jomini, a practitioner, who also a theorist and teacher.

International law, or, Rules regulating the intercourse of states in peace and war (1861; 958pp.)

This treatise very much reflected Halleck's views, as its preface states:

During the war between the United States and Mexico, the author, while serving on the staff of the commander of the Pacific squadron, and as Secretary of State of California, was often required to give opinions on questions of international law growing out of the operations of the war. As it was sometimes difficult or impossible to procure books of reference, except in the libraries of ships of war which occasionally touched at the ports of the northern Pacific, he commenced a series of notes and extracts, which were arranged under different heads, convenient for use. The manuscript so formed has been occasionally added to as new books were procured, and it is now given to the press, with the hope that it may be found useful to officers of the army and navy, and possibly, also, to the professional lawyer. With this view, a number of authorities are referred to at the end of each paragraph. It is proper to remark that these authorities are not quoted in support of the views expressed in the text, for they are sometimes directly opposed to the opinions so expressed. They will, however, be found to contain something upon the questions discussed, or upon matters immediately connected with them.
Halleck and Lieber had no substantial legal disagreements.

Weigley's two books: The American way of war;: A history of United States military strategy and policy (The Wars of the United States); and History of the United States Army (Macmillan Wars of the United States) (The Wars of the United States), should be useful background to the 18th and 19th century period covered by Witt's book and lectures.

BL: Witt's book takes us from the Limited War of the 18th century and early 19th century (i.e., limited to the battlefields, and generally avoiding civilian populations) to the Total War of the later 19th century (e.g., Sherman's Marches in Georgia and the Carolinas) and the World Wars.

- to be cont.