Pacific Blockade and vessels of third States.
§ 46. It has already been stated that those writers who admit the legality of pacific blockades are unanimous regarding the fact that no right exists for the blockading State to seize and sequestrate such ships of third States as try to break a pacific blockade. Apart from this, no unanimity exists with regard to the question of the relation between a pacific blockade and ships of third States. Some German writers[51] maintain that such ships have to respect the blockade, and that the blockading State has a right to stop such ships of third States as try to break a pacific blockade. The vast majority of writers, however, deny such right. There is, in fact, no rule of International Law which could establish such a right, as pacific in contradistinction to belligerent blockade is a mere matter between the conflicting parties. The declaration of the Institute of International Law in favour of pacific blockade contains, therefore, the condition: "Les navires de pavillons neutres peuvent entrer librement malgré le blocus."
[51] See Heffter, § 112; Perels, § 30.
The practice of pacific blockade has varied with regard to ships of third States. Before 1850 ships of third States were expected to respect a pacific blockade, and such ships of these States as tried to break it were seized, but were restored at the termination of the blockade, yet without any compensation. When in 1850 Great Britain, and likewise when in 1886 Great Britain, Austria, Germany, Italy, and Russia blockaded the Greek ports, these ports were only closed for Greek ships, and others were allowed to pass through. And the same was the case during the blockade of Crete in 1897. On the other hand, in 1894, France, during a conflict with China, blockaded the island of Formosa and tried to enforce the blockade against ships of third States. But Great Britain declared that a pacific blockade could not be enforced against ships of third States, whereupon France had to drop her intended establishment of a pacific blockade and had to consider herself at war with China. And when in 1902 Great Britain, Germany, and Italy instituted a blockade against Venezuela, they declared it a war blockade[52] because they intended to enforce it against vessels of third States.
[52] That this blockade was essentially a pacific blockade I have already stated above, [p. 50, note 1].
Pacific Blockade and vessels of the blockaded State.
§ 47. Theory and practice seem nowadays to agree upon the rule that the ships of a pacifically blockaded State trying to break the blockade may be seized and sequestrated. But they may not be condemned and confiscated, as they have to be restored at the termination of the blockade. Thus, although the Powers which had instituted a blockade against Venezuela in 1902 declared it a war blockade, all Venezuelan public and private ships seized were restored after the blockade was raised.
Manner of Pacific Blockade.
§ 48. Pacific blockade is a measure of such enormous consequences that it can be justified only after the failure of preceding negotiations for the purpose of settling the questions in dispute. And further, as blockade, being a violation of the territorial supremacy of the blockaded State, is prima facie of a hostile character, it is necessary for such State as intends in time of peace to blockade another State to notify its intention to the latter and to fix the day and hour for the establishment of the blockade. And, thirdly, although the Declaration of Paris of 1856 enacting that a blockade to be binding must be effective concerns blockades in time of war only, there can be no doubt that pacific blockades ought to be likewise effective. The declaration of the Institute of International Law in favour of pacific blockade contains, therefore, the condition: "Le blocus pacifique doit être déclaré et notifié officiellement, et maintenu par une force suffisante."
Value of Pacific Blockade.