File No. 763.72111/410
The British Ambassador (Spring Rice) to the Secretary of State
The German Government have openly entered upon the policy of arming merchant ships as commerce destroyers and even claim the right to carry out the process of arming and equipping such merchant ships in neutral harbours or on the high seas. It is in consequence of this that the British Admiralty have been compelled, in accordance with the practice followed in the great wars of history, to arm a certain number of British merchant ships for self-defence only.[Page 608]
The practice of arming ships in self-defence is very old and has been ordered by. Royal proclamation in England from early in the seventeenth century. During the Napoleonic wars the right to arm in self-defence was recognized by British and United States prize courts in the cases of the Catherine Elizabeth, (British) and the Nereide (United States). The right of a merchant ship of a belligerent to carry arms and resist capture is clearly and definitely laid down in modern times. The right of resistance of merchant vessels is recognized by the United States naval war code, by the Italian code for mercantile marine, and by the Russian prize regulations. Writers of authority in many European countries, also recognize the right. To mention a German authority, it may be stated that the late Dr. Perels, at one time legal adviser to the German Admiralty, quotes with approval Article 10 of the United States naval war code, which states: “The prisoners of merchant vessels of an enemy who in self-defence and in protection of the vessel placed in their charge resist an attack, are entitled to the status of prisoners of war.” The Institute of International Law at its meeting in 1913 prepared and adopted a manual of the laws of naval warfare, Article 10 of which expressly declared that private ships are allowed to employ force to defend themselves against the attack of an enemy’s ship.
A merchant vessel armed purely for self-defence is therefore entitled under international law to enjoy the status of a peaceful trading ship in neutral ports and His Majesty’s Government do not ask for better treatment for British merchant ships in this respect than might be accorded to those of other powers. They consider that only those merchant ships which are intended for use as cruisers should be treated as ships of war and that the question whether a particular ship carrying an armament is intended for offensive or defensive action must be decided by the simple criterion whether she is engaged in ordinary commerce and embarking cargo and passengers in the ordinary way. If so, there is no rule in international law that would justify such vessel, even if armed, being treated otherwise than as a peaceful trader.