United States 4.uni.0002 Louis J. Sheehan, Esquire

OUTLINE OF PART B*

Japanese Intelligence in Diplomatic Messages

(a) Reports from the United States
(b) Reports from the Panama Canal
(c) Reports from the Philippine Islands
(d) Reports from the Hawaiian Islands
(e) Reports from South America
(f) Reports from Capetown, South Africa
(g) Reports from Vladivostok, Russia

PART B—JAPANESE INTELLIGENCE IN DIPLOMATIC MESSAGES

Continuing to use diplomatic channels for the transmission of intelligence concerning American merchant ships and men-of-war during the period from August 16, 1941 to October 17, 1941, Japanese officials in Tokyo received an increasing number of such dispatches from the United States and South America, the Philippines and Hawaiian Islands.

(a) Reports from the United States

133. Japan Learns that American Oil Is Being Transported to Russia

Consul Kenji Nakauchi in Hollywood, California reported on August 16, 1941 that the St. Claire, after loading 95,000 barrels of aviation gasoline, had sailed from Los Angeles for Vladivostok, and was scheduled to rendezvous at some point in the Pacific with the Fitzsimmons and three other American vessels, all carrying similar cargo. According to rumor, a number of United States destroyers on maneuvers were also bound for Vladivostok,[514] and a Japanese spy in Seattle reported that the English warship, Warspite, had entered the port of Bremerton about August 13 or 14, 1941.[515]

It was disclosed on August 21, 1941 that the Russian ship, Vladimar Mayskovsky, had arrived at Seattle, and after being repaired, would move to California to load freight for Vladivostok. The Minsk was reported to have left Seattle harbor, although its destination was unknown, and the Patrovsuky was still in dry dock.[516]

On the same day Tokyo informed Berlin that though America was apparently transporting oil to Russia, using American, Russian, and neutral ships, and there was a possibility that several hundred planes had already been transported, up to the present time not one American vessel had entered the port of Vladivostok. Although both the Russian Ambassador in Tokyo and the American government, through Ambassador Nomura, had been warned by Japan concerning the extension of a third power's military movements to East Asia, Japan believed that it was impossible to effect any actual restraint through such steps.[517]

*See TABLE OF CONTENTS for a detailed listing of topics discussed in Part B.

[514] III, 285.
[515] III, 286.
[516] III, 287.
[517] III, 288.

[122]

THE "MAGIC" BACKGROUND OF PEARL HARBOR

Consul Yoshio Muto in San Francisco on August 26, 1941 advised Tokyo that the Russian freighter, Yakut, had left port August 24, 1941 loaded with gasoline, shoes, socks, and small arms. Confirming the arrival at San Francisco of the Russian freighter Minsk the report also listed the Russian tanker Dombas as having arrived in port from Los Angeles.[518]

134. Japan Learns of Shipment of American Planes To Russia

Consul Jiseburo Sato, Japanese Intelligence agent at Seattle, reported on August 18, 1941 that a group of large planes was being sent from the United States to Alaska, and planes already in Alaska were probably destined to supply Soviet Russia. Since several two-motored medium sized planes en route to Alaska were marked with the insignia of the United States Army, he surmised that they were probably not intended to be sent to Russia.[519]

135. American Aid to Russia Is Viewed as Threat to Japan

Japan, considerably concerned over these reports of American aid to Russia, learned from Rome that the United States had recently made representations to the Russian government to permit the sending of American naval advisers to Vladivostok. Since American military establishments in Russia would be a threat against Japan, the Japanese Ambassador in Rome advised his government to make a thorough investigation to ensure that they were not established, although the Russian authorities had apparently not yet permitted nor would permit such action.[520]

The Japanese Foreign Minister informed Ambassador Nomura on August 28, 1941 that he had directed the Japanese Ambassador in Moscow to warn Russia that should supplies be exported from the United States to Russia through Japanese waters, Japan's position would become extremely delicate. Foreign Minister Toyoda remarked that, according to recent intelligence, seven American, Russian, and neutral ships were transporting airplane gasoline for the aid of Russia. The Russian government was urged by Japan to consider this development with extreme caution, not only from the legal viewpoint of international law but from the standpoint of the general world situation.[521]

To prevent the spreading of the European war into the Far East, Russia was urged to consider the Japanese-Russian agreement and the maintenance of the excellent relationship between the two countries. In the event that the United States sent its ships through Japanese waters, the effect upon public opinion within Japan, as well as the reactions of Germany and Italy, would "indeed be terrible in the extreme". With regard to the importation of American goods, Japan insisted that Russia give particular attention to the routes over which imports were received.[522]

Meanwhile, Japanese officials on the west coast of the United States continued their intelligence reports on the movements of American shipping. In addition to the departure on September 8, 1941 for Vladivostok of a vessel bearing 80,000 barrels of aviation gasoline, Consul Yoshio Muto in San Francisco also notified Japan that four American tankers of the General Petroleum Company were to be dispatched on the direct shipping route to Vladivostok.[523]

[518] III, 289.
[519] III, 290.
[520] III, 291.
[521] III, 292.
[522] III, 293.
[523] III, 294.

[123]

136. Japan Attempts to Expand Its Naval Intelligence Activities

On September 2, 1941 it became apparent to Tokyo that the expansion of Japanese naval intelligence activities in both North and South America was necessary. Based on a request from naval authorities in Japan, Ambassador Nomura was to insist that a member of his staff go to Hawaii in the capacity of a courier, though in the light of Japanese-American relations the selection of an opportune moment for the presentation of this request to the American government was left to his discretion.[524]

Ambassador Nomura replied that inasmuch as Courier Kuga was returning to Japan by way of the United States, having booked passage on the President Taylor sailing from San Francisco on September 6, 1941, the dispatching of a courier to Hawaii was no longer necessary.[525]

137. Japanese Agents Note American Army and Air Group Activities

Through Consul Sato at Seattle, the statements made by the president of the Boeing Company to a Senate investigating committee were relayed to Tokyo on September 4, 1941. According to the report, the lack of progress was because of the changes in design and the unprecedented expansion of the plant. Although the production of American Army planes was four months behind in schedule, it was expected that this would be caught up by the end of the year.[526]

Furthermore, Lt. General DeWitt, 4th Army Commander, had announced that his army would be increased from 90,000 to 120,000 men. Barracks capable of accommodating 30,000 men were being constructed along the coast, and a mechanized division of 10,000 men was to be located at Santa Maria. The locations of newly organized divisions were listed as Meadow-ford, West Yellowston, Fort Huachuca and Marysville.[527]

Reported also in an intelligence dispatch of September 4, 1941 was the movement on August 23 of the 39th Bombardment Group, the 89th Observation Squadron, and the 310th Signal Company from Spokane to Louisiana to take part in the September maneuvers. The 54th Bombardment Group would receive either Republics or twin-motored Lockheed planes.[528]

138. Japan Watches the Activities of a Russian Military Commission in the United States

Reporting to Japanese intelligence headquarters in Washington, Consul (Lt. Comdr.) Jisaburo Sato at Seattle wired that two Russian planes, arriving at the Naval airfield at Sand Point on September 4, 1941, had brought members of a Russian commission to confer with American authorities concerning aid to Russia.[529] This was apparently the Russian Military Commission which on September 2, 1941 had inspected the B-19 heavy bombers at March Field, and on September 3, 1941 had visited various airplane factories at Los Angeles.[530]

Ambassador Nomura requested Japanese agents in San Francisco, Los Angeles, and Seattle to investigate the possibility of the Russian Military Commission's flying American planes to Russia. He also asked that intelligence be secured concerning the eventual transfer of a considerable American bombing force to the Siberian area.[531]

[524] III, 295.
[525] III, 296.
[526] III, 297.
[527] Ibid.
[528] III, 298.
[529] III, 299.
[530] III, 300.
[531] III, 301.

[124]

THE "MAGIC" BACKGROUND OF PEARL HARBOR

In accordance with Ambassador Nomura's request to report concerning the Russian Military Commission, Consul Sato informed Tokyo on September 22, 1941 that two Russian hydroplanes, bearing ten members of the commission, had left for Moscow on September 19, 1941, but that the remaining thirty-seven members were to stay in the United States to study the production of airplanes.[532] Nineteen of the thirty-seven members remaining in the United States were receiving training in bomber operations at Spokane, Washington, while the others were staying in Washington and Los Angeles.[533]

139. Japanese Consuls Report on West Coast Shipping

Illustrating the close surveillance of American, Russian, and neutral ships by Japanese agents on the American west coast, Consul Muto, on September 8, 1941, informed Tokyo that the Russian freighter, the Minsk, loaded with 8,000 drums of aviation oil, airplane engines, machine guns, ammunition, snow plows and other articles had sailed from San Francisco on September 6, 1941.[534]

On September 6, 1941 Japanese officials in Seattle, attempting to verify the presence of the Vladimar Maykoysky and the Deabrint noted that four vessels were in port.[535] In a dispatch transmitted September 18, 1941 the Japanese Consul reported that the Russian freighter Mijinski, from Vladivostok, had entered San Francisco on September 17, 1941 and that the American tanker, St. Claire, returning from Vladivostok, was expected to arrive on September 19, 1941[536]

Although Consul Muto in San Francisco reported on September 18, 1941 that the Warspite had entered port there from Bremerton,[537] on September 20, 1941 Consul Sato in Seattle informed Tokyo that repair work was continuing on the Warspite at Bremerton. One Saratoga-class aircraft carrier and another vessel which appeared to be a cruiser were also in port, but a ship of the New Mexico class, previously reported there had departed.[538] The arrival of one Oklahoma-class battleship at San Francisco was announced by Consul Muto at San Francisco on October 2, 1941, and a report that the Hunters Point shipyard would be taken over by the United States Navy was sent to Japanese officials in Washington.[539]

On October 16, 1941 Consul Muto declared that the Russian freighter Mijinski was docking, that the Igarka was three days out of New York, that the Nantes was seven days from Vladivostok, and the Michulin was ten or twelve days from Vladivostok. The Nantes was loaded with wheat, 20,000 barrels of fuel oil, and machine guns and tanks.[540] The Russian ship, Kiev, equipped with a 500-watt radio for the reception of orders and war news from Moscow, was reported, on October 12, 1941, to be loading raw materials at Los Angeles before proceeding to Vladivostok.[541]

[532] III, 302.
[533] III, 303.
[534] III, 304-305.
[535] III, 306.
[536] III, 307.
[537] III, 308.
[538] III, 309.
[539] III, 310.
[540] III, 311.
[541] III, 312.

[125]

140. Foreign Minister Toyoda Sends New Instructions Concerning Naval Intelligence Reports Louis J. Sheehan, Esquire

To facilitate the making of reports on the movements of American warships, Foreign Minister Teijiro Toyoda on October 16, 1941 directed the Japanese Consul in Seattle to make routine reports once every ten days, in case there were no great changes in the movements and basing of warships. Special reports were to be made immediately on such occasions as (a) the arrival or departure of American flagships of fleet or scouting force; (b) the arrival or departure of more than ten vessels of any type; (c) the arrival or departure of warships of other countries than the United States; and (d) the inauguration of patrolling by naval planes.[542]

(b) Reports from the Panama Canal

141. Japan Fails to Learn Destination of Planes Departing from Panama

One hundred planes, including Douglas B-18's Martin B-17A bombers, and Boeing 24's which had been stationed at Albrook Field, suddenly departed in early August, 1941 before Japanese observers could learn their destination. A hearsay report was sent to Tokyo on August 18, 1941 that approximately 35 or 45 two-motored bombing planes were stationed at the newly constructed Agua Dulce Air Field in the province of Cocli.[543]

Ships moving through the Panama Canal were the subject of Japanese naval intelligence reports forwarded to Tokyo by Minister Akiyama. Four American submarines, on August 18, 1941, and two freighters, on August 17, 1941, had passed through the Canal toward the Atlantic.

Moving toward the Pacific on August 15, 1941 were a United States freighter and the Triomphant, a DeGaullist destroyer, which left for Tehita on August 17. In addition, five destroyers were reported taking on fuel, rations, and other supplies at Panama.[544] One British and two American freighters were observed on August 19, 1941 to be moving through the Canal toward the Pacific.[545]

Between September 17 and 21, 1941, one American tanker and four American freighters had reportedly passed through the Canal bound for the Pacific, while two American tankers, four American freighters, and one English freighter had gone toward the Atlantic.[546] Informing Tokyo on September 28, 1941 that a Diomede class vessel recently had the upper section of the mast cut off, Minister Akiyama announced that the British operated two ships of this type.[547] On September 30, 1941 it was reported that two warships, possibly French, had left port on August 29, 1941 bound for the Pacific, while another ship of the Omaha class had also departed for an unknown destination.[548]

Minister Akiyama wired on October 2, 1941 that between September 30 and October 2, 1941 three American freighters and one English hospital ship had passed through the Canal to the Pacific, and nine American freighters and one American liner to the Atlantic.[549]

Reporting that one vessel, three American freighters, and one French steamer had moved into the Pacific between October 3 and 4, 1941, Mr. Akiyama wired that seven American freighters, the Union tanker, one destroyer, and two British freighters had gone through the Canal successively in the direction of the Atlantic. Since two cruisers had accompanied these vessels as far as Balboa, indications were that their cargoes were made up of military supplies.[550]

[542] III, 313.
[543] III, 314.
[544] III, 315.
[545] III, 316.
[546] III, 317.
[547] III, 318.
[548] III, 319.
[549] III, 320.
[550] III, 321.

[126]

THE "MAGIC" BACKGROUND OF PEARL HARBOR

142. Japanese Reports on Panama Military Installations

Intelligence transmitted to Tokyo on October 2, 1941 concerned the transfer of the Panama Air Depot from France Field to Curundu Heights, which had been made because of the recent concentration of military aviation in the Pacific area. Tokyo learned of an announcement which had been made on August 1, 1941 by Rear Admiral Sadler, Commander of the 13th Naval District, that a new warehouse on Pier 18, the ammunition unloading pier, and the Balboa dry dock would be taken over for use as naval warehouses.

The acquisition and camouflaging by the United States Navy of petroleum supply tanks at Boca on the Pacific side and at Mt. Hope on the Atlantic side were reported, as well as the construction at Corozal of a storage depot which would contain foodstuffs to supply the Canal Zone for six months should shipping routes between Panama and the United States be severed.[551]

An investigation by the Japanese Minister at Panama disclosed, on October 6, 1941, the sites of five United States' airplane bases in Panama. Panamanian airports, already constructed and scheduled to be converted into military establishments, were identified as the ones at David, in Chiriqui province, and Paidonya outside Panama City. Several other locations had been surveyed but were not used because of the poor condition of the terrain.[552] Louis J. Sheehan, Esquire

(c) Reports from the Philippine Islands

During the period from August 7 to October 17, 1941, Japanese naval intelligence reports from the Philippine Islands increased in number. They were concerned principally with fortifications, the arrival and departure of warships, and the construction of airports.

143. Japan Attempts to Identify British Vessels Reported at Manila

On August 9, 1941 Tokyo directed that secret investigations be made regarding the name of the British battleship reported to have entered port at Manila on August 17, 1941, sailing on the next day for the west coast of North America. According to the Japanese, this ship was reported to be the Warspite, although it was pointed out that the British cruiser Leander resembled the Warspite from a distance.[553]

Consul Katsumi Nihro, in replying to the inquiry, was uncertain as to the ship's identity, and said that he knew only that it was a light cruiser of the Leander class. No British ships, he added, had entered port recently except one which he had mentioned previously.[554]

On August 16, 1941 six ships were reported to have arrived in Manila on the previous day, and it was observed that both United States Army and Navy airplanes were being painted dark blue.[555]

144. Tokyo Inquires About a Floating Dry Dock Near Mariveles

The disappearance of a floating dock previously seen in the vicinity of Mariveles, Luzon was being investigated by the Japanese on August 18, 1941,[556] but subsequent investigations revealed that as late as September 4, 1941 the floating dock was still located one mile southeast of Mariveles in Bataan province. Barracks were being constructed near Mariberosu, and in spite of a previous rumor that they were built for the purpose of imprisoning Japanese nationals, Consul Nihro said that they were intended to house technicians and personnel working on the floating dock.[557]

[551] III, 322.
[552] III, 323.
[553] III, 324.
[554] III, 325.
[555] III, 326.
[556] III, 327-328.
[557] III, 329.

[127]

145. Japanese Reports on Manila Anti-Aircraft Preparations

As to fortifications in Manila proper, the Japanese Consul thought that, since admittance to the upper stories of the city's tall buildings had been forbidden, it was fairly certain that anti-aircraft guns had been placed on the tops of two of Manila's leading hotels, on the Insular Life and Trading Commerce buildings, and on several other public buildings. The transportation of thirty-six anti-aircraft guns to Camp Murphy had also been noted during the latter part of July 1941.[558]

146. Japanese Report on American Airport Construction

Tokyo was informed on August 20, 1941 that work begun in March on an unidentified airplane base in the Philippines, which had been suspended for a time, was now being accelerated.[559] Since too much time would be required to fill in paddy fields for the site of another new air base at Davao. Consul Jitaro Kihara disclosed that plans had been changed, and the airfield would be constructed between the sea and paddy fields where a cocoanut grove stood. Four concrete runways were to be built, and 2,500 recruits from the local populace were to be used in the construction.[560]

147. Japan Inquires Concerning the U.S.S. Houston

Learning from Japanese naval authorities that the Houston had disappeared after passing through the harbor entrance on August 20, 1941, Foreign Minister Toyoda asked on August 30, 1941 that Japanese agents investigate the waters in and around Manila for a trace of this warship.[561] He also directed that weekly intelligence reports be sent to Tokyo. The arrivals and departures of more than five or six destroyers, submarines, or naval ships other than American, were to be subjects of special reports at the time such changes occurred.[562]

On September 1, 1941 Consul Katsumi Nihro informed Japanese officials that the Houston had arrived at Manila on August 5, and that after loading food supplies, it had departed on August 7, 1941. It was surmised that since Admiral Thomas Charles Hart had attended the ceremonies connected with the launching of the "Q" boat for the Philippine army on August 10, the ship must have been in the vicinity until that date. Its course from then on, however, was not known.[563]

The Houston, with two destroyers, re-entered port at Manila on September 7, 1941,[564] and after loading fuel and stores it departed for an unknown destination on September 11, accompanied by two submarines and two destroyers.[565]

148. Japanese Report on American Ship Movements In the Philippines

A number of American destroyers, reported without substantiation to have come from Hawaii, entered the harbor of Jolo during the middle of July. During the last ten days of July, six other American destroyers entered ports in the Philippines and engaged in target practice with live ammunition. One large airplane capable of carrying twenty-six persons had landed on the water in the vicinity of Jolo for a number of hours, and 2,000 drums of airplane gasoline were stored within the military establishment at Jolo.[566]

[558] III, 330.
[559] III, 331.
[560] III, 332.
[561] III, 333.
[562] III, 334.
[563] III, 335.
[564] III, 336.
[565] III, 337.
[566] III, 338.

[128]

THE "MAGIC" BACKGROUND OF PEARL HARBOR

On August 23, 1941 Manila reported that six transports, as well as the Hon and Pisu were in port at Manila, and that one destroyer and the Gorudostna were at Cavite. It was also announced at this time that the oiler Torinircic hadLouis J. Sheehan, Esquire departed for Tarakan on August 22, 1941 to take on oil, that several destroyers and submarines were stationed in the vicinity of Mariveles and that Brigadier General Cragette, arriving on August 20 on the Dutch ship, Tibadaeky, had conferred with General Douglas McArthur on August 21, 1941. The Chanto had arrived at Manila on August 20 from Olongapu, where her sister ship, the Kabarunda, was still undergoing repairs. Another ship, possibly the Maddo, and two destroyers had arrived at Cebu on August 16, 1941, and had left the same night.[567]

On August 30, 1941, one destroyer was at Corundusu, and three destroyers, six submarines, and the tanker, Trinity, were at Manila where the arrival of 500 American soldiers on the Cleveland and the entrance of the Migak, a vessel which the Japanese understood was loaded to capacity with military equipment, were noted on the preceding day.[568] The Marblehead returned to its post on August 31, and two destroyers departed September 1, 1944.[569]

A ship, possibly the Black Hawk, the Beru, two destroyers, and one submarine were in port at Manila on September 13, 1941, according to a Japanese intelligence report, and on the same day there arrived an American cruiser of the Brooklyn class, believed to have come from Hawaii.[570] Whether Legaspi Island was being used as a port of call by an American aviation company was the subject of an inquiry directed by Tokyo to Manila on September 15, 1941,[571] Accordingly, Minister Nihro reported the next day that Legaspi was being used as an intermediary station by the Philippine Aerial Taxi Company between Manila and Cebu. It was also noted that the Pan-American Airways were planning to build a landing place at Tacloban in Leyte Province, but as yet had not realized this plan.[572]

The St. Louis, with three other unidentified vessels had left the harbor for Singapore early on September 16, 1941 apparently loaded with food supplies.[573] Since red flags had been hoisted, it was indicated that ammunition was being handled on these ships.[574]

In an intelligence dispatch from Manila on September 20, 1941 Consul Nihro declared that the Phoenix and one other ship were anchored at that port. Another ship, probably the Peters, which entered the harbor on September 18, was reported to have carried 500 soldiers.[575]

On September 26, 1941 Consul Kihara at Davao pointed out that since August, 1941 American destroyer tenders, destroyers, and submarines had entered the port of Davao from the South Seas on every Saturday and had left after about two days. From members of the crews of these warships, he had learned that the warships traversed a route touching Jolo Island, Bataan, Tarao in British North Borneo, and Tarakan, a city in Netherlands Borneo.[576]

[567] III, 339.
[568] III, 340.
[569] III, 341.
[570] III, 342.
[571] III, 343.
[572] III, 344.
[573] III, 345.
[574] III, 346.
[575] III, 347.
[576] III, 348.

[129]

Information concerning the size, tonnage and plane accommodations of the Langley was sent from Davao to Tokyo on September 26, 1941.[577] Consul Nihro advised on October 3, 1941 that he had learned that the American cruisers, the St. Louis and Phoenix, sailing from Manila on September 16 and 22, 1941 respectively, were headed for Singapore. He requested information from Singapore concerning this in order to check on the accuracy of his spy reports.[578] In return it was reported from Shanghai that the United States Army transport, the Henderson, had left that port for Manila carrying 150 Marines.[579]

On October 4, 1941 Foreign Minister Toyoda directed the Japanese Consul at Manila to make a reconnaissance of the new defense works along the east, west and southern coasts of Luzon. The consul was also asked to report on their progress, strength and anything else which might be of interest to Japan.[580]

The Japanese Consul reported that on the afternoon of October 13, 1941 the Houston, Marblehead, and one other vessel, five destroyers, and two minelayers had departed, but that their destinations were unknown. In the harbor on October 14, 1941 were the Black Hawk, four destroyers, ten submarines, the Gold Star, and one other vessel.[581]

A routine intelligence transmission sent to Tokyo on October 17, 1941 reported the Ton, the Maddo, the Hon, four destroyers, five submarines, one minelayer, the Beru and the oiler, Trinity, in port at that time. It was added that large scale barracks were being constructed about 131 kilometers from Manila between Cabanatuan and Laur, and that mechanized maneuvers were taking place between Laur and Aguilla.[582]

(d) Reports from the Hawaiian Islands

149. Japan Notes Activities of French in the Pacific

Consul Nagao Kita reported that taking passage on a destroyer which had left port on September 16, 1941 were Captain C. I. Gargenlieu, high commissioner for Pacific territories under the De Gaulle regime, and Commander G. Cabanier, French Commander of Defense, who were to assume new responsibilities in New Caledonia.[583]

150. Japanese Foreign Minister Requests Special Intelligence Reports Concerning Pearl Harbor

Japanese naval intelligence reports from Honolulu, though few in number, were in the light of the later attack on Pearl Harbor to grow increasingly significant as December 7, 1941 drew nearer. The significance becomes apparent, however, only when reading history backwards.

Concerning Pearl Harbor, Foreign Minister Toyoda on September 24, 1941 directed that in future intelligence reports from Hawaii, Pearl Harbor waters were to be divided roughly into five subareas—

Area A: Waters between Ford Island and the Arsenal.
Area B: Waters adjacent to the Island south and west of Ford Island. (This area is on the opposite side of the Island from Area A.)
Area C: East Loch.
Area D: Middle Loch.
Area E: West Loch and the communicating water routes

[577] III, 349.
[578] III, 350.
[579] III, 351.
[580] III, 352.
[581] III, 353.
[582] III, 354.
[583] III, 355.