§ 350. In contradistinction to supply to belligerents by neutrals, such supply by subjects of neutrals is lawful, and neutrals are not, therefore, obliged according to their duty of impartiality to prevent such supply. Article 7 of Convention V. and article 7 of Convention XIII. concur in enacting the old customary rule that "A neutral Power is not bound to prevent the export or transit, 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 fleet." And article 18[689] of Convention V. recognises the fact that the furnishing of supplies to a belligerent by such subjects of neutrals as do not live on the territory of the other party, or on the territory occupied by that party, does not invest these individuals with enemy character. When in August 1870, during the Franco-German War, Germany lodged complaints with the British Government for not prohibiting its subjects from supplying arms and ammunition to the French Government, Great Britain correctly replied that she was not by International Law under the obligation to prevent her subjects from committing such acts. Of course, such neutral as is anxious to avoid all controversy and friction can by his Municipal Law order his subjects to abstain from such acts, as for instance Switzerland and Belgium did during the Franco-German War. But such injunctions arise from political prudence, and not from any obligation imposed by International Law.
[689] That Great Britain has entered a reservation against article 18, and the portent of this reservation, has been pointed out above, in § [88, p. 109, note 1].
The endeavour to make a distinction between supply in single cases and on a small scale on the one hand, and, on the other, supply on a large scale, and to consider only the former lawful,[690] has neither in theory nor in practice found recognition. As International Law stands, belligerents may make use of visit, search, and seizure to protect themselves against conveyance of contraband by sea to the enemy by subjects of neutrals. But so far as their neutral home State is concerned, such subjects may, at the risk of having their property seized during such conveyance, supply either belligerent with any amount of arms, ammunition, coal, provisions, and even with armed ships,[691] provided always that they deal with the belligerents in the ordinary way of commerce.
[690] See Bluntschli, § 766.
[691] See above, § [334], and below, § [397].
The case is different when there is no ordinary commerce with a belligerent Government and when subjects of neutrals directly supply a belligerent army or navy, or parts of them. If, for instance, a belligerent fleet is cruising outside the maritime belt of a neutral, the latter must prevent vessels of his subjects from bringing coal, arms, ammunition, and provisions to that fleet, for otherwise he would allow the belligerent to make use of neutral resources for naval operations.[692] But he need not prevent vessels of his subjects from bringing coal, arms, ammunition, and provisions to belligerent ports, although the supply is destined for the navy and the army of the belligerent. He need not prevent belligerent merchantmen from coming into his ports and carrying arms and the like, bought from his subjects, over to the ports of their home State. And he need not prevent vessels of his subjects from following a belligerent fleet and supplying it en route[693] with coal, ammunition, provisions, and the like, provided such supply does not take place in the neutral maritime belt.
[692] See above, § 333 (4).
[693] See above, § [311, p. 375, note 4].
There is no doubt that, as the law stands at present, neutrals need not prevent their subjects from supplying belligerents with arms and ammunition. Yet, on the other hand, there is no doubt either that such supply is apt to prolong a war which otherwise would come to an end at an earlier date. But it will be a long time, if ever it happens, before it is made a duty of neutrals to prevent such supply as far as is in their power, and to punish such of their subjects as engage in it. The profit derived from such supply being enormous, the members of the Family of Nations are not inclined to cripple the trade of their subjects by preventing it. And belligerents want to have the opportunity of replenishing with arms and ammunition if they run short of them during war. The question is merely one of the standard of public morality.[694] If this standard rises, and it becomes the conviction of the world at large that supply of arms and ammunition by subjects of neutrals is apt to lengthen wars, the rule will appear that neutrals must prevent such supply.
[694] See above, [vol. I. § 51 (6)] p. 83.