Traditionally, neutrality on the part of a State not a party to the war has consisted in refraining from all participation in the war, and in preventing, tolerating, and regulating certain acts on its own part, by its nationals, and by the belligerents. It is the duty of belligerents to respect the territory and rights of neutral States.
In the event of any threat to the peace, breach of the peace, or act of aggression, the Security Council of the United Nations is authorized, under Articles 39 through 42 of the Charter, to make recommendations, to call for the employment of measures short of force, or to take forcible measures to maintain or restore international peace and security. Measures short of force or force itself may also be employed in pursuance of a recommendation of the General Assembly of the United Nations. Although these provisions of the Charter have not made it impossible for a State to remain neutral, the obligations which the Charter imposes have to a certain extent qualified the rights of States in this respect. For example, if a State is called upon, under Articles 42 and 43 of the Charter, to take military action against an aggressor, that State loses its right to remain neutral but actually loses its neutrality only to the extent that it complies with the direction of the Security Council.
A military commander in the field is obliged to respect the neutrality of third States which "are not allied with the United States in the conduct of hostilities and are not violating their duty of neutrality toward this country, except to the extent that the State concerned has expressly qualified its neutrality.
a. Treaty Provisions. See Articles 2 and 3, H. III (pars. 21 and 22).
b. Proclamations of Neutrality. When war occurs, neutral States usually issue proclamations of neutrality, in which they state their determination to observe the duties of neutrality and warn their nationals of the penalties they incur for joining or assisting a belligerent.
a. Treaty Provisions.
The territory of neutral Powers is inviolable. (H. V, art. 1.)
b. Application of Role. The foregoing rule prohibits any unauthorized entry into the territory of a neutral State, its territorial waters, or the airspace over such areas by hoops or instrumentalities of war. If harm is caused in a neutral State by the unauthorized entry of a belligerent, the offending State may be required, according to the circumstances, to respond in damages.
Belligerents are forbidden to move troops or convoys of either munitions of war or supplies across the territory of a neutral Power. (H. V, art. 2.)
A distinction must be drawn between the official acts of the belligerent State in convoying or shipping munitions and supplies through neutral territory as part of an expedition and the shipment of such supplies by private persons. The former is forbidden while the latter is not.
A neutral Power must not allow any of the acts referred to in Articles II to IV to occur on its territory.
It is not called upon to punish acts in violation of its neutrality unless the said acts have been committed on its own territory. (H. V, art. 5.)
a. Treaty Provision.
The fact of a neutral Power resisting, even by force, attempts to violate its neutrality cannot be regarded as a hostile act. (H. V, art. 10.)
b. Patrolling the Frontier. In order to protect its neutrality, a State whose territory is adjacent to a theater of war normally mobilizes a portion of its forces to prevent troops of either belligerent from entering its territory, to intern such as maybe permitted to enter, and generally to carry out its duties of neutrality.
Should the neutral State be unable, or fail for any reason, to prevent violations of its neutrality by the troops of one belligerent entering or passing through its territory, the other belligerent may be justified in attacking the enemy forces on this territory.
Supplementing the rules of international law, there are certain statutes of the United States that define offenses against neutrality and prescribe penalties therefor, some of which are effective only during a war in which the United States is neutral, and others of which are effective at all times (see 18 U. S. C. 956-968, 22 U. S. C. 441-457, 461-465). The enforcement of these statutes devolves primarily upon the civil authorities, but under certain circumstances land or naval forces may be employed for that purpose (see, e. g., 22 U. S. C. 46l).
a. Treaty Provision.
Corps of combatants cannot be formed nor recruiting agencies opened on the territory of a neutral Power to assist the belligerents. (H. V, art. 4.)
b. Application of Rule. The establishment of recruiting agencies, the enlistment of men; the formation and organization of hostile expeditions on neutral territory, and the passage across its frontiers of organized bodies of men intending to enlist are prohibited.
c. Personnel of Voluntary Aid Societies. This prohibition does not extend to medical personnel and units of a voluntary aid society duly authorized to join one of the belligerents. (See GWS, art. 27; par. 229 herein.)
The responsibility of a neutral Power is not engaged by the fact of persons crossing the frontier separately to offer their services to one of the belligerents. (H. V, art. 6.)
a. Individual Persons Crossing the Frontier. The prohibition in Article 4, H. V (par. 522), is directed against organized bodies which only require to be armed to become an immediate fighting force. Neutral States are not required to enact legislation forbidding their nationals to join the armed forces of the belligerents. Individuals crossing the frontier singly or in small bands that are unorganized similarly create no obligation on the neutral State. The foregoing rules do not, however, permit a State professing to be neutral to send regularly constituted military units across the frontier in the guise of "volunteers" or small unorganized bands.
b. Nationals of Belligerent Not Included. Nationals of a belligerent State are permitted freely to leave neutral territory to join the armies of their country.
A neutral Power is not called upon to prevent the export or transport, on behalf of one or other of the belligerents, of arms, munitions of war, or, in general, of anything which can be of use to an army or a fleet. (H. V, art. 7.)
Although a neutral State is not required to prohibit the shipment by private persons of supplies or munitions of war, the neutral State, as such, is prohibited from furnishing such supplies or munitions and from making loans to a belligerent. It is also forbidden to permit the use of its territory for the fitting out of hostile expeditions.
Commercial transactions with belligerents by neutral corporations, companies, citizens, or persons resident in neutral territory are not prohibited. A belligerent may purchase from such persons supplies, munitions, or anything that may be of use to an army or fleet, which can be exported or transported without involving the neutral State.
Belligerents are likewise forbidden:
a. To erect on the territory of a neutral Power a wireless telegraphy station or any apparatus for the purpose of communicating with belligerent forces on land or sea;
b. To use any installation of this kind established by them before the war on the territory of a neutral Power for purely military purposes, and which has not been opened for the service of public messages. (H. V, art. 3.)
A neutral Power is not called upon to forbid or restrict the use on behalf of the belligerents of telegraph or telephone cables or of wireless telegraphy apparatus belonging to it or to Companies or private individuals. (H. V, art. 8.)
The liberty of a neutral State, if it so desires, to transmit messages by means of its telegraph, telephone, cable, radio, or other telecommunications facilities does not imply the power so to use them or to permit their use as to lend assistance to the belligerents on one side only.
Every measure of restriction or prohibition taken by a neutral Power in regard to the matters referred to in Articles VII and VIII must be impartially applied by it to both belligerents.
A neutral Power must see to the same obligation being observed by Companies or private individuals owning telegraph or telephone cables or wireless telegraphy apparatus. (H. V, art. 9.)
A neutral Power which receives on its territory troops belonging to the belligerent armies shall intern them, as far as possible, at a distance from the theatre of war.
It may keep them in camps and even confine them in fortresses or in places set apart for this purpose.
It shall decide whether officers can be left at liberty on giving their parole not to leave the neutral territory without permission. (H. V, art. 11.)
A neutral is not bound to permit belligerent troops to enter its territory. On the other hand, it may permit them to do so without violating its neutrality, but the troops must be interned or confined in places designated by the neutral. They must be disarmed and appropriate measures must be taken to prevent their leaving the neutral country. In those cases in which the States concerned are parties to GPW, Article 4, paragraph B(2), thereof requires that such persons, provided they are otherwise entitled to be treated as prisoners of war, are, as a minimum but subject to certain exceptions, to receive the benefit of treatment as prisoners of war under GPW (see par. 61).
If troops or soldiers of a belligerent are permitted to seek refuge in neutral territory, the neutral is authorized to impose the terms upon which they may do so. In case of large bodies of troops seeking refuge in neutral territory, these conditions will usually be stipulated in a convention drawn up by the representatives of the neutral power and the senior officer of the troops.
Officers and men interned in a neutral State may in the discretion of that State be released on their parole under conditions to be prescribed by the neutral State. If such persons leave the neutral State in violation of their parole, the State in whose armed forces they serve is obliged to return them to the neutral State at its request.
The munitions, arms, vehicles, equipment, and other supplies which the interned troops are allowed to bring with them into neutral territory are likewise detained by the neutral State. They are restored to the State whose property they are at the termination of the war.
In the absence of a special Convention the neutral Power shall supply the interned with the food, clothing, and relief required by humanity.
At the conclusion of peace the expenses caused by the internment shall be made good. (H. V, art. 12.)
A neutral Power which receives escaped prisoners of war shall leave them at liberty. If it allows them to remain in its territory it may assign them a place of residence.
The same rule applies to prisoners of war brought by troops taking refuge in the territory of a neutral Power. (H. V, art. 13.)
A neutral Power may authorize the passage over its territory of wounded or sick belonging to the belligerent armies, on condition that the trains bringing them shall carry neither personnel or material of war. In such a case, the neutral Power is bound to take whatever measures of safety and control are necessary for the purpose.
The wounded or sick brought under these conditions into neutral territory by one of the belligerents, and belonging to the hostile party, must be guarded by the neutral Power so as to ensure their not taking part again in the operations of the war. The same duty shall devolve on the neutral State with regard to wounded or sick of the other army who may be committed to its care. (H. V, art. 14.)
Subject to the provisions of the second paragraph, medical aircraft of Parties to the conflict may fly over the territory of neutral Powers, land on it in case of necessity, or use it as a port of call. They shall give the neutral Powers previous notice of their passage over the said territory and obey all summons to alight, on land or water. They will be immune from attack only when flying on routes, at heights and at times specifically agreed upon between the Parties to the conflict and the neutral Power concerned.
The neutral Powers may, however, place conditions or restrictions on the passage or landing of medical aircraft on their territory. Such possible conditions or restrictions shall be applied equally to all Parties to the conflict.
Unless agreed otherwise between the neutral Power and the Parties to the conflict, the wounded and sick who are disembarked, with the consent of the local authorities, on neutral territory by medical aircraft, shall be detained by the neutral Power, where so required by international law, in such a manner that they cannot again take part in operations of war. The most of their accommodation and internment shall be borne by the Power on which they depend. (GWS, art. 37.)
The neutral power is under no obligation to permit the passage of a convoy of sick and wounded through its territory, but when such a convoy is permitted to pass, the neutral must exercise control, must see that neither personnel nor material other than that necessary for the care of the sick and wounded is carried, and generally must accord impartiality of treatment to the belligerents.
The sick and wounded of a belligerent maybe carried through neutral territory to the territory of the belligerent State. If, however, they are left in the neutral's territory, they must be interned so as to insure their not taking part again in the war.
Sick and wounded prisoners of war brought into neutral territory by the Detaining Power as part of a convoy of evacuation granted right of passage through neutral territory may not be transported to their own country or liberated, as are prisoners of war escaping into, or brought by troops seeking asylum in neutral territory, but must be detained by the neutral power, subject to the provisions contained in paragraphs 188 through 196.
a. Placed on a Neutral Warship or Aircraft.
If wounded, sick or shipwrecked persons are taken on board a neutral warship or a neutral military aircraft, it shall be ensured, where so required by international law, that they can take no further part in operations of war. (GWS sea, art. 15.)
b. Landed in Neutral Ports.
Wounded, sick or shipwrecked persons who are landed in neutral ports with the consent of the local authorities, shall, failing arrangements to the contrary between the neutral and the belligerent Powers, be so guarded by the neutral Power, where so required by international law, that the said persons cannot again take part in operations of war.
The costs of hospital accommodation and internment shall be borne by the Power on whom the wounded, sick or shipwrecked persons depend. (GWS sea, art. 17.)
The medical personnel and chaplains (as defined in GWS, art. 24; par. 67 herein) belonging to belligerent forces who have sought asylum under Article 11, H. V (par. 532), may be retained and are required to be released as prescribed in Articles 28 and 80, GWS (pars. 230 and 231). Medical personnel and materials necessary for the care of the sick and wounded of a convoy of evacuation, permitted to pass through neutral territory under Article 14, H. V (par. 539), may be permitted to accompany the convoy. Subject to the provisions of Articles 28 and 30, GWS, the neutral State may retain the necessary medical personnel and materiel for the care of the sick and wounded left in its care. Failing this, it must furnish such personnel and materiel, and the expense thereof must be refunded by the belligerent concerned not later than at the termination of the war.
Articles 109 through 117, GPW, authorize parties to the conflict to conclude arrangements with neutral States for the accommodation of the seriously wounded and sick and persons who have undergone a long period of captivity. See paragraphs 188 through 196 for provisions in this regard, including direct repatriation of certain wounded and sick from the neutral country.
The nationals of a State which is not taking part in the war are considered as neutrals. (H. V, art. 16.)
Neutral persons resident in occupied territory are not entitled to claim different treatment, in general, from that accorded the other inhabitants. They must refrain from all participation in the war, from all hostile acts, and observe strictly the rules of the occupant. All nationals of neutral powers, whether resident or temporarily visiting an occupied territory, may be punished for offenses committed by them to the same extent and in the same manner as enemy nationals. (See GC, art. 4; par. 247 herein, regarding the protection of neutral persons.)
Diplomatic agents of neutral States must be treated with all courtesy and must be permitted such freedom of action as it is possible to allow, with due regard to the necessities of the war. The same is true of consular personnel of neutral States, except those who are enemy nationals.
a. Treaty Provision.
A neutral cannot avail himself of his neutrality:
a. If he commits hostile acts against a belligerent.
b. If he commits acts in favour of a belligerent, particularly if he voluntarily enlists in the ranks of the armed force of one of the parties.
In such a case, the neutral shall not be more severely treated by the belligerent as against whom he has abandoned his neutrality than a national of the other belligerent State could be for the same act. (H. V, art. 17.)
b. Offenses in Occupied Territory. Nationals of neutral States, whether resident in or visiting occupied territory, may be punished for offenses in the same manner as enemy nationals. They may be deported or expelled for just cause. In the event that such a person is arrested, suspicions must be verified by a serious inquiry, and the arrested neutral person must be given an opportunity to defend himself, and to communicate with the consul of his country if he requests it.
The following acts shall not be considered as committed in favour of one belligerent in the sense of Article XVII, letter b:
a. Supplies furnished or loans made to one of the belligerents, provided that the person who furnishes the supplies or who makes the loans lives neither in the territory of the other party nor in the territory occupied by him, and that the supplies do not come from these territories;
b. Services rendered in matters of police or civil administration. (H. V, art. 18.)
Railway material coming from the territory of neutral Powers, whether it be the property of the said Powers or of Companies or private persons, and recognizable as such, shall not be requisitioned or utilized by a belligerent except where and to the extent that it is absolutely necessary. It shall be sent back as soon as possible to the country of origin.
A neutral Power may likewise, in case of necessity, retain and utilize to an equal extent material coming from the territory of the belligerent Power.
Compensation shall be paid by one party or the other in proportion to the material used, and to the period of usage. (H. V, (art. 19.)