740.00117 Pacific War/61

The Department of State to the Spanish Embassy


The Department of State refers to memorandum no. 148 of June 28, 1943 from the Spanish Embassy16 in charge of Japanese interests in the continental United States and to the Department’s preliminary reply of July 6, 194317 regarding alleged attacks on six Japanese hospital ships.

The United States Government has caused a detailed investigation to be made of the alleged attacks on the six Japanese hospital ships and, as a result thereof, the following determinations have been made:
Arabia Maru: On 4 January 1943 airplanes dropped bombs on a vessel, described as a transport, in the Rangoon River scoring hits and near misses, as a result of which heavy smoke was billowing up from this vessel when last seen. The Japanese protest refers to bombs dropped adjacent to the alleged hospital ship. The alleged jeopardy to the hospital ship must have arisen, therefore, from its proximity to a military target.
America Maru: Enemy shipping in Rabaul Harbor was attacked by airplanes at 0505 on 30 January 1943 and at 1205 on the same date an airplane attack was made against a transport in the open bay. On neither occasion was any hospital ship or illuminated vessel observed in the area referred to in the Japanese protest. The Japanese allege the attack as occurring at 0420 and if it occurred it must, therefore, have been as a result of the presence of the hospital ship in proximity to military targets and without identifying illumination.
Manila Maru: On 4 March 1943 in the area stated, but at 1257–1301, torpedoes were fired at a zigzagging light grey Japanese vessel during a rain squall. The ship was not painted as prescribed for hospital ships by the Hague Convention.18
Urabu Maru: An airplane attack was made on a vessel near Kavieng at 1600 on 3 April 1943. At the time of sighting this vessel, the aircraft concerned was at a height of 6,000 feet. The crew of the aircraft did not observe any of the conventional markings which indicated a hospital ship, but did see what appeared to be a canvas-covered gun position forward. From the photographs taken during the attack, it is not possible to distinguish with the naked eye any hospital ship insignia and only in one of these can such insignia be distinguished by the aid of a magnifying glass. No insignia appears [Page 1148] from an overhead position, and no Red Cross flag was flown. The absence of distinctive and obvious markings from overhead made it quite impossible for the aircraft to determine the special status of this vessel and the presence on the deck of what appeared to be a gun, added strength to the presumption that the vessel was other than a hospital ship.
Huso Maru: No operation by a United Nations aircraft has been reported against any ship on 15 April 1943 in any area adjacent to the alleged location. On 16 April a night attack was made upon Kahili and Ballale where previous reconnaissance had revealed the presence of a number of warships and cargo vessels, presenting a legitimate military target. Among the targets attacked was a large ship, subsequently identified as a hospital ship. Illumination of the hospital ship was such that its identity was not apparent above 2,000 feet. The attack was abandoned immediately after identification.
Buenos Aires Maru: The Japanese report alleges an attack by submarine near Hongkong at 1545 on 25 April 1943. No United States submarine nor, as far as this Government is aware, any other United Nations submarine made an attack in the general vicinity of Hongkong on this date.
The Armed Forces of the United States are under strict instructions to observe scrupulously the terms of the Hague Convention applicable to hospital ships and to accord all due immunity to such vessels. The United States Government is satisfied that these instructions are complied with to the limit permitted by the compliance of Japanese hospital ships with their reciprocal obligations. The fact that the conventions are known to the personnel of the Armed Forces and that such personnel make every effort to observe them is demonstrated by repeated reports of the sighting of hospital ships which have not been molested when recognized as such.
It must be pointed out, furthermore, that international law expressly recognizes certain circumstances under which belligerents may be unable to accord immunity to hospital ships. These circumstances arise, for example, when a hospital ship at its own risk and peril stations itself in the vicinity of a legitimate military target whether in port or on the high seas, or when a hospital ship fails to provide itself with adequate and clearly visible markings and illuminations as it is under obligation to do by the terms of Article 5 of the Hague Convention.
The United States Government regrets that accidental attacks should have been made upon Japanese hospital ships. But the attacks alleged appear to be definitely attributable to the failure of the Japanese authorities either to insure the identification of their hospital ships or to remove those ships from the immediate vicinity of legitimate military targets, or to both causes.
The United States Government, while for the above reasons rejecting entirely the protests made by the Japanese Government, desires [Page 1149] to assure the Japanese Government that it has every intention of continuing to respect the immunity of hospital ships in accordance with its assumed obligations and international practice. It is observed, however, that it is not always possible for aircraft to distinguish the identification for hospital ships prescribed by the Hague Convention. The United States Government points out that the markings prescribed by the Hague Convention must be considered the minimum rather than the maximum requirements, and that at the time they were prescribed the circumstances of naval warfare only were envisaged.
The United States Government has accordingly taken steps to place upon its hospital ships markings additional to those prescribed by the Hague Convention and in order to facilitate their identification as such in the light of the conditions of modern warfare, has adopted the following policies, the adoption of which with respect to Japanese hospital ships should similarly facilitate their identification:
In order to acquire right to immunity at night, hospital ships must be illuminated continuously from sunset to sunrise.
In order to acquire right to immunity at night, the funnels and hulls of hospital ships must be illuminated from sunset to sunrise to show the Red Crosses, white painting and green band. Distinctive markings which must at all times be displayed on the decks for identification from the air must be similarly illuminated at night.
If markings are not illuminated at the time of an attack at night, no complaint can be entertained. It is not, however, illegal for a hospital ship to darken ship at her own risk on necessary occasions such as when lying in a port, passing through defensive minefields or in company with the fleet.
The United States Government notes that the altered markings of certain Japanese military hospital ships, as well as the provision for their illumination at night, which are described in the Embassy’s memorandum no. 329 (Ex. 111.00) of November 8, 1943,19 are similar in nature to those referred to in subparagraph 66 above.
  1. Ibid., p. 1036.
  2. Not printed; but see footnote 58, ibid., p. 1037.
  3. Convention for the Adaptation to Naval War of the Principles of the Geneva Convention, signed at The Hague, October 18, 1907, Foreign Relations, 1907, pt. 2, p. 1229. The Geneva Convention for the Amelioration of the Condition of the Wounded in Armies in the Field was signed July 6, 1906, ibid., 1906, pt. 2, p. 1559.
  4. Not printed.