Voluntary and Conventional Neutrality.
§ 302. A third distinction is that between voluntary and conventional neutrality. Voluntary (or simple or natural) is the neutrality of such State as is not bound by a general or special treaty to remain neutral in a certain war. Neutrality is in most cases voluntary, and States whose neutrality is voluntary may at any time during the war give up their attitude of impartiality and take the part of either belligerent. On the other hand, the neutrality of such State as is by treaty bound to remain neutral in a war is conventional. Of course, the neutrality of neutralised States is in every case conventional. Yet not-neutralised States can likewise by treaty be obliged to remain neutral in a certain war, just as in other cases they can by treaty of alliance be compelled not to remain neutral, but to take the part of one of the belligerents.
Armed Neutrality.
§ 303. One speaks of an armed neutrality when a neutral State takes military measures for the purpose of defending its neutrality against possible or probable attempts of either belligerent to make use of the neutral territory. Thus, the neutrality of Switzerland during the Franco-German War was an armed neutrality. In another sense of the term, one speaks of an armed neutrality when neutral States take military measures for the purpose of defending the real or pretended rights of neutrals against threatening infringements on the part of either belligerent. The First and Second Armed Neutrality[565] of 1780 and 1800 were armed neutralities in the latter sense of the term.
[565] Se above, §§ [289] and [290].
Benevolent Neutrality.
§ 304. Treaties stipulating neutrality often stipulate a "benevolent" neutrality of the parties regarding a certain war. The term is likewise frequently used during diplomatic negotiations. However, at present there is no distinction between benevolent neutrality and neutrality pure and simple. The idea dates from earlier times, when the obligations imposed by neutrality were not so stringent, and neutral States could favour one of the belligerents in many ways without thereby violating their neutral attitude. If a State remained neutral in the then lax sense of the term, but otherwise favoured a belligerent, its neutrality was called benevolent.
Perfect and Qualified Neutrality.
§ 305. A distinction of great practical importance was in former times that between perfect, or absolute, and qualified, or imperfect, neutrality. The neutrality of a State was qualified if it remained neutral on the whole, but actively or passively, directly or indirectly, gave some kind of assistance to one of the belligerents in consequence of an obligation entered into by a treaty previous to the war, and not for the special war exclusively. On the other hand, a neutrality was termed perfect if a neutral State neither actively nor passively, and neither directly nor indirectly, favoured either belligerent. There is no doubt that in the eighteenth century, when it was recognised that a State could be considered neutral, although it was by a previous treaty bound to render more or less limited assistance to one of the belligerents, this distinction between neutrality perfect and qualified was justified. But during the second half of the nineteenth century it became controversial whether a so-called qualified neutrality was neutrality at all, and whether a State, which, in fulfilment of a treaty obligation, rendered some assistance to one of the belligerents, violated its neutrality. The majority of modern writers[566] maintained, correctly I think, that a State was either neutral or not, and that a State violated its neutrality in case it rendered any assistance whatever to one of the belligerents from any motive whatever. For this reason, a State which had entered into such obligations as those just mentioned would in time of war frequently be in a conflict of duties. For, in fulfilling its treaty obligations, it would frequently be obliged to violate its duty of neutrality, and vice versa. Several writers,[567] however, maintained that such fulfilment of treaty obligations would not contain a violation of neutrality. All doubt in the matter ought now to be removed, since article 2 of Convention V. of the Second Peace Conference categorically enacts that "belligerents are forbidden to move across the territory of a neutral Power troops or convoys either of munitions of war or of supplies." The principle at the back of this enactment no doubt is that a qualified neutrality has no longer any raison d'être, and that neutrality must in every case be perfect.[568]
[566] See, for instance, Ullmann, § 190; Despagnet, No. 685; Rivier, II. p. 378; Calvo, IV. § 2594; Taylor, § 618; Fiore, III. No. 1541; Kleen, I. § 21; Hall, § 215 (see also Hall, § 219, concerning passage of troops). Phillimore, III. § 138, goes with the majority of publicists, but in § 139 he thinks that it would be too rigid to consider acts of "minor" partiality which are the result of conventions previous to the war as violations of neutrality.