[69] See, for instance, Hall, § 18, p. 74, and Westlake, Chapters, p. 262.
[70] It is of value to quote articles 20-26 of the Instructions for the Government of Armies of the United States in the Field, which the War Department of the United States published in 1863 during the War of Secession with the Southern member-States:
(20) "Public war is a state of armed hostility between sovereign nations or governments. It is a law and requisite of civil existence that men live in political, continuous societies, forming organised units, called States or nations, whose constituents bear, enjoy, and suffer, advance and retrograde together, in peace and in war."
(21) "The citizen or native of a hostile country is thus an enemy as one of the constituents of the hostile State or nation, and as such is subjected to the hardships of war."
(22) "Nevertheless, as civilisation has advanced during the last centuries, so has likewise advanced, especially in war on land, the distinction between the private individual belonging to a hostile country and the hostile country itself, with its men in arms. The principle has been more and more acknowledged that the unarmed citizen is to be spared in person, property, and honour as much as the exigencies of war will admit."
(23) "Private citizens are no longer murdered, enslaved, or carried off to distant parts, and the inoffensive individual is as little disturbed in his private relations as the commander of the hostile troops can afford to grant in the overruling demands of a vigorous war."
(24) "The almost universal rule in remote times was ... that the private individual of the hostile country is destined to suffer every privation of liberty and protection and every disruption of family ties. Protection was ... the exception."
(25) "In modern regular wars ... protection of the inoffensive citizens of the hostile country is the rule; privation and disturbance of private relations are the exceptions."
(26) "Commanding generals may cause the magistrates and civil officers of the hostile country to take the oath of temporary allegiance or an oath of fidelity to their own victorious Government or rulers, and they may expel every one who declines to do so. But, whether they do so or not, the people and their civil officers owe strict obedience to them as long as they hold sway over the district or country, at the peril of their lives."
War a contention between States for the purpose of overpowering each other.