The inhabitants of a country engaged in war are divided into two classes: combatants and non-combatants.

"Combatants, in the full sense, are the regularly authorized military and naval forces of the states. They are liable to the risks and entitled to the immunities of warfare, and if captured become prisoners of war.

"(a) The status of combatants is also allowed to two classes which engage in defensive hostilities.

"(1) The officers and crew of a merchant vessel which defends itself by force are liable to capture as prisoners of war.

"(2) With regard to levies en masse much difference of opinion exists. Article 10 of the Declaration of Brussels, 1884, was adopted at the Hague Conference in 1899, and may be considered as representing a generally accepted position, namely: The population of a non-occupied territory, who, on the approach of the enemy, of their own accord take up arms to resist the invading troops, without having had time to organize themselves in conformity with Article 9 (providing responsible leader, uniform, etc.), shall be considered as belligerents, if they respect the laws and customs of war.'

"(b) The status of combatants is not allowable for those who, without state authorization, engage in aggressive hostilities."11

Non-combatants are subject to the ordinary hardships occasioned by warfare but cannot be made prisoners of war. If a non-combatant engages in hostile acts against the enemies he is liable to any punishment which the enemy may choose to inflict upon him, even death.

"Spies are those who, acting secretly or under false pretenses, collect or seek to collect information in the districts occupied by the enemy, with the intention of communicating it to the opposing force. Such agents are not forbidden, but are liable to such treatment as the laws of the capturing army may prescribe. This may be death by hanging. The office of spy is not necessarily dishonorable."12