With the exercise of the greatest ingenuity and utmost resourcefulness, regarded by the committee as meriting the highest commendation, the War and Navy Departments collaborated in breaking the Japanese diplomatic codes. Through the exploitation of intercepted and decoded messages between Japan and her diplomatic establishments, the so-called Magic, a wealth of intelligence concerning the purposes of the Japanese was available in Washington. [113]

Both the Army and Navy maintained several stations throughout the United States and in the Pacific for the purpose of intercepting Japanese radio communications. These stations operated under instructions mandating from Washington and forwarded the intercepted traffic to Washington without themselves endeavoring to decode or translate the material. The only exception to this procedure was in the case of the Corregidor station which had been provided with facilities for exploiting many of the Japanese diplomatic messages in view of its advantageous location from the standpoint of intercepting Tokyo traffic. [114]

Insofar as the commanding officers in Hawaii were concerned they received none of the Magic save as it was supplied them by the War and Navy Departments in the original, paraphrased, or captioned form or, operationally, through instructions predicated on this source of intelligence. While the highest military officials in Washington did not know the precise nature of radio intelligence activities in Hawaii, it is clear that those charged with handling the Magic did not

[109] See statement of Mr. Stimson, committee record, p. 14418. Also committee exhibits Nos. 16,17. [110] Admiral Stark was asked: "Was not that our intention (of doing anything possible to prevent war with the Japanese) right up to December 7, if it could be done without sacrificing American honor and principles?"

He replied: "Yes, sir, and we had been working for months on that, and the record is complete in that regard." Committee record, p. 13915. [111] See committee record, pp. 13741, 13742. [112] See Secretary Hull's replies to committee interrogatories. Committee record, p. 14266. [113] See committee exhibits Nos. I and 2. For a discussion of Magic and its great significance to the prosecution of the war see letters dated September 25 and 27, 1944, from General Marshall to Governor Dewey. Committee record pp. 2979-2989. [114] For a discussion of the mechanics of the Magic see testimony of Admiral Noyes and Capts. L. F Safford and A. D. Kramer of the Navy, and Cols. Otis K. Sadtler and Rufus Bratton of the Army; before the committee.

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rely upon either the Army or Navy in Hawaii being able to decode the diplomatic messages which were decoded in Washington. However both Admirals Stark and Turner testified that they were under the impression that Japanese diplomatic messages were being decode by the Navy in Hawaii. [115] No justification for this impression existed in fact apart from the failure of these officers to inform themselves adequately concerning Navy establishments. [116] Under arrangements existing during 1941 between the Army and the Navy in Washington the decoding and translating of Magic was divided between the Army Signal Intelligence Service under the direction of the Chief Signal Officer and a unit in the Navy, known as OP-20-G, under the control of the Director of Naval Communications. The responsibility for decoding and translating messages was allocated between the two services on the basis of the dates of the messages with each service ordinarily handling all messages originated on alternate days, the Army being responsible for even dates and the Navy, for odd dates This procedure was flexible in that it was departed from in order to expedite the handling of material as the occasion demanded or in the case of any unusual situation that might prevail in one or the other of the services.

POLICY WITH RESPECT TO DISSEMINATION OF MAGIC

The Magic intelligence was regarded as preeminently confidential and the policy with respect to its restricted distribution was dictated by a desire to safeguard the secret that the Japanese diplomatic codes were being broken. [117] Delivery of the English texts of the intercepted messages was limited, within the War Department, to the Secretary of War, the Chief of Staff, the Chief of the War Plans Division, and the Chief of the Military Intelligence Division; within the Navy, to the Secretary of Navy, the Chief of Naval Operations, the Chief of the War Plans Division, and the Director of Naval Intelligence; to the State Department; and to the President's naval aide for transmittal to the President. By agreement between the Army and Navy in Washington, the Army was responsible for distribution of Magic within the War Department and to the State Department; the Navy, for distribution within the Navy Department and to the White House. Any disclosure of the fact that the Japanese messages were being decoded or any disclosure of information obtainable only from that source would inevitably have resulted in Japan's changing her codes with attendant loss completely of the vital Magic. This fact was responsible for the translated material being closely held among a

[115] See committee record, p. 5095. [116] Admiral Stark testified: "I inquired on two or three occasions as to whether or not Kimmel could read certain dispatches when they came up and which we were interpreting and sending our own messages and I was told that he could. *However, I want to make it plain that that did not influence me in the slightest regarding what I sent*. I felt it my responsibility to keep the commanders in the field and to see to it that they were kept informed of the main trends and of information which (would) be of high interest to them. Regardless of what dispatches I might have seen, they may have formed background for me but I saw that affirmative action was taken from the Chief of Naval Operations to the commanders in the field on matters which I thought they should have." Committee record, p. 5793 [117] During the course of his testimony, General Miles was asked: "Who made the decision that these messages should not be sent to Hawaii as they were intercepted and translated as far as the Army is concerned?"

He replied: "That followed from the general policy laid down by the Chief of Staff that these messages and the fact of the existence of these messages or our ability to decode them should be confirmed to the least possible number of persons; no distribution should be made outside of Washington. * * *

"The value of that secret, the secret that we could and did decode Japanese messages, in their best code, was of incalculable value to us, both in the period when war threatened and most definitely during our waging of that war. That was the basic reason for the limitation on the distribution of those messages and of the constantly increasing closing in, as I might express it, on any possible leaks in that secret." Committee record, pp. 2092, 2093.

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few key individuals, in addition necessarily to those who processed the messages.

The policy generally prevailed in the days before Pearl Harbor that the Magic materials were not ordinarily to be disseminated to field commanders. [118] This policy was prescribed for the reason that (1) the Japanese might conceivably intercept the relayed Magic intelligence and learn of our success in decrypting Japanese codes: [119] (2) the volume of intercepted traffic was so great that its transmission, particularly during the critical period of diplomatic negotiations, would have overtaxed communication facilities; and (3) responsibility for evaluation of this material which was largely diplomatic in nature was properly in Washington, where the Magic could be considered along with other pertinent diplomatic information obtained from the State Department and other sources. There was no inflexible rule, however, which precluded sending to theater commanders in proper instances, either in its original form as paraphrased or in the form of estimates, conclusions, or orders based wholly or in part upon Magic. Important information derived therefrom was from time to time sent to the Hawaiian commanders by the Navy Department in paraphrased form or in the form of estimates. [120] The War Department, on the other and, did not send the Magic to the field, for the reason that the Army code was not believed to be as secure as that of the Navy. [121]

For purposes of the investigation Magic fell generally into two categories: first, messages relating to diplomatic matters of the Japanese Government; [122] and second, messages relating to espionage activities by Japanese diplomatic representatives, particularly with respect to American military installations and establishments. [123]

The decision not to endeavor to supply field commanders all of the Magic intelligence as such was a reasonable one under the circumstances. However, it is incumbent to determine whether responsible commanding officers were otherwise supplied the equivalent of intelligence obtained from the Magic materials.

"SHIPS IN HARBOR" REPORTS NATURE OF CONSULAR ESPIONAGE

In addition to the Magic materials relating strictly to diplomatic negotiations, a great many messages between Japan and her diplomatic establishments were intercepted reflecting espionage activities by the consular staffs. [124] These intercepts related in the main to instructions sent by Tokyo and replies pursuant thereto concerning the movement and location of American ships and the nature of military and defensive installations.

[118] For a discussion concerning this matter, see letter dated April 22, 1941, from Capt. Arthur N. McCollum in Washington to Capt. Edwin T. Layton, Pacific Fleet intelligence officer. Committee record, pp. 12917-12923. [119] This factor applied principally to the Army. See testimony of General Miles. Note 121, infra. [120] See committee exhibit No. 37, pp. 4-12, 40, 41. [121] In testifying concerning the matter of distributing Magic to field commanders General Miles was asked; "Do I understand from your answer that these messages intercepted and translated were not sent to Hawaii by the Army?"

He replied: "They were not. In some cases the substance of some messages were sent to Hawaii, and all most always in naval code, I think always in naval code, because the naval code was considered to be more secure than the Army code." Committee record, pp. 2091, 2092. [122] Committee exhibit No. 1. [123] Id., No. 2. [124] Id.

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The Hawaiian commanders have strongly insisted that messages to and from the Japanese Consulate in Honolulu clearly indicated Japan's intention to attack the fleet at Pearl Harbor. They contend they were wrongfully deprived of this information, basing this contention to a great extent on an intercepted dispatch from Tokyo of September 24, 1941 [125] issuing the following instructions to its Honolulu Consulate: [126]

"Strictly secret.

"Henceforth, we would like to have you make reports concerning vessels along the following lines insofar as possible:

"1. The waters (of Pearl Harbor) are to be divided roughly into five subareas (We have no objections to your abbreviating as much as you like.)

"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 communication water routes.

"2. With regard to warships and aircraft carriers, we would like to have you report on those at anchor (these are not so important) tied up at wharves, buoys and in docks. (Designate types and classes briefly. If possible we would like to have you make mention of the fact when there are two or more vessels along side the same wharf.) [127]"

The foregoing message, No. 83, has been gratuitously characterized throughout the proceedings as the "bomb plot message", the "harbor berthing plan", and by similar terms. Three other intercepted messages relate in a pertinent manner to the September 24 dispatch and to Tokyo's interest in the fleet at Pearl Harbor:

(1) In a message from Tokyo to the Honolulu Consul, dated November 15, 1941 (translated December 3, 1941) it was stated: [128]

"As relations between Japan and the United States are most critical make your "ships in harbor report" irregular, but at a rate of twice a week. Although you already are no doubt aware, please take extra care to maintain secrecy."

(2) An intercept from Tokyo dated November 20, 1941 (translated December 4) read: [129]

"Please investigate comprehensively the fleet-bases in the neighborhood of the Hawaiian military reservation."

(3) An intercept of November 29 (translated December 5) stated: [130]

"We have been receiving reports from you on ship movements, but in future will you also report even when there are no movements?"

Referring to the indicated messages, Admiral Kimmel testified: [131]

"In no other area was the Japanese Government seeking information as to whether two or more vessels were alongside the same wharf. Prior to the dispatch of September 24, the information which the Japanese sought and obtained about Pearl Harbor followed the general pattern of their interest in American Fleet movements in other localities. One might suspect this type of conventional espionage. With the dispatch of September 24, 1941, and those which followed there was a significant and ominous change in the character of the information

[125] Translated October 9. [126] Committee exhibit No. 2, p. 12. [127] Some of the subsequent reports from the Japanese Consulate in Honolulu were made pursuant to the instructions contained in the September 24 dispatch from Tokyo. See committee exhibit No. 2 pp. 13 and 14. [128] Committee exhibit No. 2, p. 13. [129] Id., at p. 15. Captain Kramer testified with respect to the blank, a garble, in this message between the words "fleet" and "bases" that he believed the original Japanese version in ungarbled form if it were available would read: "Please investigate comprehensively the fleet air bases." Committee record, pp. 1162-1163 [130] Committee exhibit No. 2, 15 p. [131] Committee record, pp. 6779, 6780.

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which the Japanese Government sought and obtained. The espionage then directed was of an unusual character and outside the realm of reasonable suspicion. It was no longer merely directed to ascertaining the general whereabouts of ships of the fleet. It was directed to the presence of particular ships in particular areas; to such minute detail as what ships were double-docked at the same wharf. In the period immediately preceding the attack, the Jap Consul General in Hawaii was directed by Tokyo to report even when there were no movements of ships in and out of Pearl Harbor. *These Japanese instructions and reports pointed to an attack by Japan upon the ships in Pearl Harbor*. The information sought and obtained with such painstaking detail had no other conceivable usefulness from a military viewpoint. Its utility was in planning and executing an attack upon the ships in port. Its effective value was lost completely when the ships left their reported berthings in Pearl Harbor."

In the same connection General Short testified: [132]

"While the War Department G-2 may not have felt bound to let me know about the routine operations of the Japanese in keeping track of our naval ships, they should certainly have let me know that the Japanese were getting reports of the exact location of the ships in Pearl Harbor, which might indicate more than just keeping track, *because such details would be useful only for sabotage, or for air or submarine attack in Hawaii*. As early as October 9, 1941, G-2 in Washington new of this Japanese espionage. *This message, analyzed critically, is really a bombing plan for Pearl Harbor*."

In endeavoring to evaluate the intercepted dispatch of September 4 and related dispatches, it is to be borne in mind that the Japanese were insistent in their desire to secure information concerning the location and movements of American vessels everywhere and not merely at Pearl Harbor. There are no other dispatches before the committee, however, in which *Tokyo* manifested an interest concerning the disposition of ships *within* a harbor, as in the case of the "berthing plan," as distinguished from the desire to know whether a vessel was at a particular harbor. Viewing the September 24 instructions to her Honolulu consul in this light, it would appear that Tokyo vas manifesting an unusual interest in the presence of our Pacific fleet and the detailed location thereof in Pearl Harbor.

The evidence reflects, however, that no one in Washington attached he significance to the "berthing plan" which it is now possible to read into it. To determine whether failure to appreciate the plan represents a lack of imagination and a dereliction of duty, we consider now the contentions of the officers who saw this intelligence before December 7, 1941, and the circumstances under which it was received in Washington.

At the time the "berthing plan" was translated, the practice was being followed by Captain Kramer of preparing a gist of intercepted messages to expedite consideration of them by recipients. [133] Asterisks were employed along with the gist to provide an indication of the significance of messages--one asterisk meant "interesting messages"; two asterisks, "especially important or urgent messages." [134] The gist relating to the berthing plan read: [135] "Tokyo directs special reports In ships with(in) Pearl Harbor which is divided into five areas for the purpose of showing exact location" and was indicated by one asterisk

[132] Id., at p. 7989 [133] The practice of preparing gists is indicated to have been discontinued during the month of November 1941, for the reason that the President insisted on seeing the original messages "because he was afraid when they tried to condense them, someone would change the meaning." See testimony of Captain Safford, Hewitt Inquiry Record, p. 408, also Clarke Inquiry Exhibit No. 23. [134] Committee record pp. 11206, 11207. [135] Id., at pp. 11207, 11208.

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as being an "interesting message". In explaining his estimate of the message, Captain Kramer testified: l36

"* * * Your interpretation, Senator, that this was a bombing map, I do not believe, from conversations I had at the time in showing and going over days' traffic with various recipients; I do not believe it was interpreted by any of those persons as being materially different than other messages concerning ship movements being reported by the Japanese diplomatic service.

"I recollect that this was interpreted. I am uncertain of the precise wording of the interpretation. This was considered, and *I believe it was, approximately, my consideration at the time as being an attempt on the part of the Japanese diplomatic service to simplify communications.*

"That view is substantiated by many factors.

"One is that the Japanese were repeatedly and continually directing their diplomatic service to cut down traffic. They were repeatedly preparing and sending out abbreviations to be used with codes already in existence. Diplomatic codes were frequently asking for additional funds for quarterly allotments, and so forth to cover telegraphic expenses. Those expenses were usually paid and furnished in part when so requested by Tokyo. Those and other considerations I think explain, probably, the handling of this particular message, sir."

Upon being asked what evaluation he placed on the harbor berthing plan and related intercepts, Admiral Wilkinson testified: [137]

"The Japanese for many years had the reputation, and the facts bore out that reputation, of being meticulous seekers for every scrap of information, whether by photography or by written report or otherwise.

"We had recently, as reported to me, apprehended two and I think three Japanese naval officers on the west coast making investigations of Seattle, Bremerton, Long Beach, and San Diego. In the reports that we had gotten from them there had been indications of movements and locations of ships; in the papers that they had there were instructions for them to find out the movements and locations of ships except in Hawaii and the Philippines, the inference being that these fellows that were planted in America, these naval officers, were not to be responsible for movements in Hawaii and the Philippines because there were agencies finding that information there.

"My general impression of adding all this reputation and this fact and these data together was that these dispatches were part of the general information system established by the Japanese. We knew also that certain information had been sought in Panama and again in Manila. I did not, I regret now, of course attribute to them the bombing target significance which now appears."

And again: [138]

"* * * the location of the ship, whether it was alongside of a dock or elsewhere, did give an inference of work going on aboard her which would be of value to the question of when she might be moved, what her state of readiness was and the inference that we drew from this was that they wanted to know everything they could not only about the movement of the ships and those that were present and, therefore, accounted for and not a threat to them in some other waters, but also with reference to those that were present where they were located with reference to state of repair. For instance, the ships that were particularly in Pearl Harbor might be in repair and not ready to go to sea, whereas those at anchor in the stream would be ready, or would be so on short notice. Those at doublebanked piers might not be, particularly the inside one might take some time to go out."

Admiral Wilkinson thought he had mentioned to one or more officers that the Japanese seemed curious as to the lay-port in Pearl Harbor and testified "at the time I thought that that was an evidence of their nicety of intelligence." [139]

On the other hand, Admiral Stark, who stated he had no recollection of having seen the berthing plan and accompanying messages prior to the attack, testified: [140]

[136] Id., at p. 1160. [137] Id., at pp. 4620, 4621. [138] Id., at pp. 4622, 4623. [139] Id., at p. 4624. [140] Id., at pp. 5788, 5789.

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"These messages are of a class of message which gives positions of ships in harbor, gives locations. The message, however, is distinctly different from the usual type of ship report, which simply would say, "So many ships" or give their names, in Pearl Harbor. This dispatch is different in that it calls for the location of ship in the harbor in her particular berth.

"I recall no such request from Tokyo to the field; that is, to the Japanese people, to report like that except for Pearl Harbor. There might have been. We did not see it. I believe there are one or two places were ships were reported like in Puget Sound, in a certain berth or a dock, alongside of a dock, but this dispatch while of a class is of a character which is different.

"In the light of hindsight it stands out very clearly, with what we can read into now, as indicating the possibility or at least the ground work for a Japanese raid on Pearl Harbor. That significance which we now have in the light of hindsight was not pointed out to me by anyone, nor do I have the slightest recollection of anybody ever having given that significance at the time."

Asked if he felt significance should have been attached to the plan at the time it was received, Admiral Stark said: [141]

"It is very difficult to separate hindsight from foresight. I can only say that it went through our people, it went through the Army, who were likewise vitality interested in the defense of Pearl Harbor, and I do not recollect anyone having pointed it out. There was literally a mass of material coming in. We knew the Japanese appetite was almost insatiable for detail in all respects. The dispatch might have been put down as just another example of their great attention to detail.

"If I had seen it myself I do not know what I would have done. I might have said, "Well, my goodness, look at this detail," or I might have read into it because it is different, I might have said, "Well, this is unusual. I wonder why they want it?" I might have gone on, and diagnosed it or I might not. I simply did not know. We read it now in the light of what has happened."

Captain McCollum, [142] who was not in Washington at the time the harbor berthing plan was intercepted or translated, suggested certain reasons why the plan would not have been interpreted as a "bombing plot." [143] He observed that beginning in 1935 the Japanese Navy was apparently not satisfied with the type of intelligence forwarded by the consular agents and in consequence undertook to set up an observation net of its own, particularly on the west coast of the United States, but that it was his feeling the Japanese had been unable to put naval observers into the consulate at Honolulu. Therefore. As he testified: [144]

"As we estimated it, the consul general at Honolulu was receiving, through the Foreign Office at the instance of the Japanese Naval Department, explicit directions of the type of intelligence that was needed, much more in detail than any of the other key consulates on the west coast, because he did not have the benefit of the services of a Japanese Naval Intelligence officer within his consulate.

"Therefore this thing here, if I saw it, I am quite certain I would have felt it was just another move to get explicit information, to cut down the frequently voluble type of reports made by consular officials which the Jap Navy did not like."

Captain McCollum further pointed out that the matter of how ships were anchored and where they were anchored was designed to indicate the facility with which the fleet was prepared to *sortie*, considering that the anchorage at Pearl Harbor is "chopped up" into a number of more or less independent locks. He testified: [145]

"To give a general statement of where the ships were, the stuff they are requiring here, would require a rather long-winded dispatch, where the same device such as breaking it up into areas A, B, and C, such a simple device could be used. With

[141 Id., at pp. 5790, 6791. [142] Capt. Arthur N. McCollum, Chief of the Far Eastern Section of Naval Intelligence. [143] Captain McCollum left Washington on September 24 and did not return until October 11. Committee record, p. 9195. [144] Committee record, pp. 9140, 9141. [145] Id., at pp. 9178, 9179.

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this area discovered, a rather simple and short dispatch would suffice to give the essential information as to the location of the fleet and also an indication of their readiness for sortie. I would suggest that that is a reasonable, tenable hypothesis as to why they wished information, apparently, in this detail."

In summary, Captain McCollum stated he would not now necessarily regard the harbor berthing plan as a "bombing plan" unless "I had known Pearl Harbor had been bombed." [140]

It appears clear that there were many other messages between Tokyo and her consulates, received in Washington, indicating a likely Japanese purpose to attack at points other than at Hawaii. [147]

These messages indicate a definite interest in the state of defenses at many points. A dispatch from Tokyo on October 16 to its Seattle consul instructed "Should patrolling be inaugurated by naval planes report it at once." [148] In the same message the Consulate was instructed to report on the movement and basing of warships at least once every 10 days, "As long as there is no great change," but a report was to be submitted "Should more than 10 vessels of any type arrive or depart from port at one time." A June 23, 1941 dispatch from Tokyo to Mexico instructed: [149] "Regarding the plans for procuring maps of the Panama Canal and vicinity, please have career attache Kihara make an official trip to Panama * * *. Have the maps taken out by plane, and then have Sato, the naval attache, bring them to Tokyo with him when he returns." While no instructions from Tokyo to Panama are available subsequent to August 2, 1941, the reports to Tokyo contain detailed information concerning the location of airfields, air strength, ammunition, location and camouflage of petroleum supply tanks, location and strength of artillery patrols, radar detectors and their range, map procurement and other matters which would obviously be of interest only if an attack on the Panama Canal were contemplated. [150] While some of these messages were translated after December 7, they have a distinct bearing on whether, before the event, the harbor berthing plan was reasonably designed to be a harbinger of the December 7 attack. [151]

With respect to other messages concerning defenses, Tokyo on August 1 requested Manila to obtain information "regarding the camouflage and distinguishing marks of the American naval and military aeroplanes in Manila". [152] On October 4 Tokyo instructed Manila "to make a reconnaissance of the new defense works along the east, west, and southern coasts of the Island of Luzon, reporting on their progress, strength, etc." [153] Tokyo instructed Manila on November 5, pursuant to a request of the "Naval General Staff", to obtain information with respect to each port of call concerning "(1) conditions at airports on land", "(2) types of planes at each, and number of planes", "(3) warships; also machinery belonging to land forces", and "(4) state or progress being made on all equipment and establishments." [154] On November 15 Tokyo requested Manila to "make investigations again" as to the number of large bombers in

[146] Id., at p. 9141. [147] See committee exhibit No. 2. [148] Id., at p. 111. [149] Id., at p. 122. [150] Id., at pp. 31-52 [151] General Marshall stated he was always in fear of a surprise attack on United States territory but the probabilities pointed to the Panama Canal and to the Philippines before Hawaii. Navy Court of inquiry record, p. 863. [152] Committee exhibit No. 2, p. 54. [153] Id., at p. 72. [154] Id., at p. 82,

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the Philippines. [155] Some 50 messages between Manila and Tokyo during the period August 1 to December 1, 1941, contained detailed information concerning airfields, air strength and activity, strength and activity of land forces, location of antiaircraft guns, and other items of defense. [156]

Seattle advised Tokyo on September 20 that a warship under repair at Bremerton, Wash. Had "the upper part of the bridge and left side of the bow spotted here and there with red paint". [157] A message of September 6 from Tokyo to Singapore and Batavia requested detailed information concerning various types of fishing vessels should Japan "require the use of these fishing vessels". [158] On October 22 a message from Tokyo to Singapore reflected a specific request, on behalf of the vice chief of the Japanese General Staff, for information concerning the air forces stationed in the Federated Malay States. [159] Another dispatch from Tokyo to Batavia on the same day stated that the Assistant Chief of Staff desired an inspection and report "on the air force in the Dutch Indies" in regard to training, information, and aerial combat methods; organization, types, number, and location of planes; and types and number of planes being sent from England and the United States. [160]

The exhibits are replete with evidence of the interest of Tokyo not only in the state of defenses but in ships as well, at many different points. For example, an intercepted dispatch from Tokyo to San Francisco of November 29 read: [161] "Make full report beginning December 1 on the following: Ship's nationality, ship's name, port from which it departed (or at which it arrived), and port of destination (or from where it started), date of departure, etc., in detail of all foreign commercial and war ships now in the Pacific, Indian Ocean, and South China Sea." Nor was the Honolulu consul the only one reporting the exact location of ships in harbor. Manila advised Tokyo on November 12 that on the morning of the 12th, an American cruiser of the Chester class entered port--"She is tied up at dock No. 7 * * *." [162] And again on November 22, Manila advised Tokyo, among other things, that a camouflaged British cruiser entered port In the "morning of the 21st and anchored at pier No. 7 * * *." [163] Other examples of such reports will be hereinafter set forth.

Even today, of course, we do not know as a matter of fact that the "berthing plan" was a bomb plot. On the basis of testimony before he committee, the desire to know or the supplying of information with respect to the location of vessels *within* a harbor is not of itself conclusive that its only purpose was in contemplation of an attack inasmuch as such information also has the value of indicating what ships are under repair and the readiness of vessels for sortie. [164] For example, Seattle advised Tokyo on September 20, "Saratoga class aircraft carrier, 1 ship (*tied up alongside the pier*)" at Bremerton. [165] San Francisco advised Tokyo on October 2, "One Oklahoma class battle-

[155] Id., at p. 91. [156] Id., at pp. 54-98. [157] Id., at p. 109. [158] Id., at p. 101. [159] Id.. at p. 102. [160] Id.. at p. 102. [161] Id.. at p. 115. [162] Id.. at p. 87. [163] Id.. at p. 94. [164] See Committee record, pp. 4622, 4623, 9178, and 9179. [165] Committee exhibit No. 2, p. 109.

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ship has arrived in port and is *moored in front of the Bethlehem shipbuilding yard*. [166] It may be argued that if obtaining information concerning the location of ships within a harbor should be construed as definitely indicating a purpose to attack the ships at harbor then these messages would logically appear to indicate a purpose to attack at Bremerton and at San Francisco.

In seeking to determine whether the harbor berthing plan was in reality a "bomb plot" it is noted that in making his report of December 5 [167] and his last report of December 6 [168] to Tokyo concerning vessels at Pearl Harbor, the Honolulu consul did not employ the system established in the plan for indicating the location of ships within the harbor. In the report of December 5, he said:

" * * * the following ships were in port on the afternoon of the 5th: 8 battleships, 3 light cruisers, 16 destroyers * * *."

In the last report, the consul said:

"On the evening of the 5th, among the battleships which entered port were (garble) and one submarine tender. The following ships were observed at anchor on the 6th: 9 battleships, 3 light cruisers, 3 submarine tenders, 17 destroyers and in addition there were 4 light cruisers, 2 destroyers lying at docks (the heavy cruisers and airplane carriers have all left) * * *."

Failure to use the plan for indicating the location of ships within the harbor at the only time when it could have materially assisted the attacking force in locating ships as targets for bombing, that is on December 5 and 6 immediately before the attack, raises a serious question as to whether the berthing plan was in reality a bomb plot at all.

Japanese interviewed since VJ-day have asserted that intelligence obtained from the consulates was regarded as of little importance. They did not include the intelligence under discussion in listing the information which the Task Force employed in planning and executing the attack on December 7. [168a]

The record reflects that no one in Washington interpreted the harbor berthing plan of September 24 and related dispatches as indicative of an attack on the fleet at Pearl Harbor or was in any way conscious of the significance of the messages which it is now possible to read into them. There was in consequence no conscious or deliberate withholding of this intelligence from the Hawaiian commanders. General Marshall, and Admirals Stark, Turner, and Ingersoll testified they had no recollection of having seen these dispatches. [169]

The peculiar division of Pearl Harbor into many lochs, the insatiable desire of Japan for meticulous information concerning vessels of other governments everywhere, the manner in which the berthing plan lent itself to convenience of communications, the fact that Tokyo was repeatedly instructing its consulates to cut down on traffic, the feeling in Washington that Tokyo had no naval observer in Honolulu and in consequence more detailed instructions to its consulate there were required, Japan's natural interest in full information concerning our Pacific Fleet base, the many intercepted dispatches indicating a likely

[166] Id., at p. 110. [167] Id., at p. 26. [168] Id., at p. 29. [168a] See Part II, this report concerning Japanese plans for the attack; also section "The Role of Espionage in the Attack", Part III, this report. [169] Committee record, pp. 2912, 5788, 5108, and 11311. Admiral Stark said: "We have been over this bomb plot thing from start to finish, all of us in the front office, and I still not only have no recollection of having seen it, it is my honest opinion that I did not see it." Committee record, p. 13969.

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Japanese attack at points other than at Pearl Harbor--all of these considerations necessarily entered into the appraisal of the berthing an. It may be contended that under such circumstances it would be manifestly unfair to criticize an officer with many other responsibilities [170] for failure to interpret properly a message, considered before the critical turn in our negotiations with Japan, which we single out after the event for minute analysis and conclude may have been designed to assist the Japanese in the bombing of Pearl Harbor. [171]

Similarly, it may be argued that the absence of apparent interest by Japan in the defenses at Hawaii when compared with the avid interest manifested in the defense facilities in the Philippines, Panama, Singapore, Batavia, and on the west coast is indicative, in the days before December 7, of the fact that Hawaii was a much less likely point of attack than these other places; and that in this light, Tokyo's detailed interest in our ship locations and movements was subject to the reasonable construction that Japan desired to be warned in advance any contemplated action by our fleet and was not seeking information with a view to an attack upon it or, otherwise stated, that she desired information with a view to the fleet's availability for distant operations rather than its susceptibility as a target. [172] Further, that Pearl Harbor was the base of the Pacific Fleet, the only substantial deterrent to complete freedom of action by the Japanese Navy in Pacific waters and that in consequence thereof an unusual interest by Japan in the location of our fleet units would appear quite understandable. It may be proper to insist that since Pearl Harbor was the fleet base, Japan could be reasonably sure that substantial fleet units would be located there at virtually all times; [173] and that, with this in mind, failure to manifest an interest in the defenses of Hawaii when compared with such an interest shown at other points has a distinct bearing on whether the information exchanged between Tokyo and Honolulu concerning ship locations and movements could have pointed in any way to likelihood of an attack at Pearl Harbor. In this connection, the evidence does reflect that none of the intercepted messages translated before the attack, between Tokyo and Honolulu for over a year prior to December 7, contain any reference to the defenses of the Army or Navy in Hawaii as distinguished from locations of fleet units.

From these considerations it may be contended that a careful comparison and evaluation of messages relating to espionage activities by Japan's diplomatic establishments would not have reasonably indicated in the days before December 7 any greater likelihood of an attack on Pearl Harbor than was warned against in the dispatches sent the Hawaiian commanders on November 27. [174]

CONCLUSIONS WITH RESPECT TO SHIPS IN HARBOR REPORTS

Despite the foregoing observations, we think there are certain circumstances which distinguish the request for detailed information on

[170] See committee record, pp. 2131-2138. [171] General Miles observed: "* * * this message taken alone would have been of great military significance but it was not taken alone unless you look at it by hindsight, which focuses all light on the event which did happen. It was one of a great number of messages being sent by the Japanese to various parts of the world in their attempt to follow the movements of our naval vessels, a matter which we knew perfectly well they were doing, and which we ourselves were doing in regard to the Japanese." Committee record, p. 2100. [172] See Hewitt Inquiry record, p. 407 [173] This appears to be the premise assumed by the Japanese in planning and launching the attack. See Part II, this report. [174] Committee exhibits Nos. 32 and 37, pp. 9 and 36, respectively.

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the berthings of ships in Pearl Harbor from similar or other requests for information concerning other points. War with Japan was admittedly probable for months before it actually occurred. Many of our highest military and naval authorities considered it all but inevitable. As the imminence of war increased so increased the importance of our Pacific Fleet, the home base of which was Pearl Harbor, for in the broad picture of the Pacific, the fleet was our strong arm of defense. Safety and fitness of the Pacific Fleet was of prime importance, and any communication or information bearing thereon should have been given prompt and full consideration by competent authority. We realize the exceedingly great demands upon the intelligence divisions of the War and Navy Departments occasioned by reason of the great flood of intelligence coming in from all parts of the world in the days before Pearl Harbor. Nor do we overlook the Japanese policy of acquiring detailed information of every kind from many points. It may be fair to attribute to this and other considerations the failure to see anything of unusual significance in the request of September 24 for detailed information as to the berthing of ships in Pearl Harbor; but it is difficult to escape the feeling that, when the message of November 15 was translated on December 3 referring to the critical relations between Japan and the United States and requesting that the "ships in harbor report" be made irregularly but at least twice a week and directing that extra care be taken to maintain secrecy, it should have raised in someone's mind the thought that this intelligence was highly important because it dealt with that which was most vital to our safety in the Pacific--the Pacific Fleet. The message of November 20, translated December 4, directing a comprehensive investigation of "the fleet (garble) bases" in the neighborhood of the Hawaiian military reservation should not have lessened such interest. [175]

It cannot be forgotten that a surprise attack by air on Pearl Harbor had been listed and understood, both in Washington and Hawaii, as the greatest danger to that base. We must assume that military men realized that in order to execute successfully such an attack the Japanese would necessarily need detailed information as to dispositions at the point of attack. It would seem to be a natural consequence that if Japan undertook an attack on Pearl Harbor she would seek to acquire such detailed information and in point of time as nearly as possible to the hour of such attempt.

We are unable to conclude that the berthing plan and related dispatches pointed directly to an attack on Pearl Harbor, nor are we able to conclude that the plan was a "bomb plot" in view of the evidence indicating it was not such. [176] We are of the opinion, however, that the berthing plan and related dispatches should have received careful consideration and created a serious question as to their significance. Since they indicated a particular interest in the Pacific Fleet's base this intelligence should have been appreciated and supplied the commander in chief of the Pacific Fleet and the commanding general of the Hawaiian Department for their assistance, along with other information and intelligence available to them, in making their estimate of the situation.

[175] It may be argued that the fact that a "war warning" had been sent the Fleet on November 27 along with the code destruction intelligence before these latter messages were translated had a bearing on or possibly conditioned the failure to attach significance to them. [176] Admiral Kimmel said: "These Japanese instructions and reports pointed to an attack by Japan upon the ships in Pearl Harbor." Committee record, pp. 6779, 6780.

General Short said: "* * * such details would be useful only for sabotage, or for air or submarine attack on Hawaii." Committee record, p. 7989.

PEARL HARBOR ATTACK 191

THE "WINDS CODE" [177]

On November 19, 1941, Tokyo set up a code designed to be employed in daily Japanese language short-wave news broadcasts or general intelligence broadcasts in the event ordinary commercial channels of communication were no longer available. Two circular [178] dispatches Nos. 2353 and 2354 were translated by the Navy Department: [179]

"From: Tokyo "To: Washington 9 November 1941 Circular #2353 " "Regarding the broadcast of a special message in an emergency.

"In case of emergency (danger of cutting off our diplomatic relations), and the cutting off of international communications, the following warnings will be added n the middle of the daily Japanese language short-wave news broadcast.

"(1) In case of a Japan-U. S. relations in danger: HIGASHI NO KAZEAME. [1] "(2) Japan-U. S. S. R. relations: KITA NO KAZE KUMORI. [2] "(3) Japan-British relations: NISHI NO KAZE HARE. [3]

"This signal will be given in the middle and at the end as a weather forecast and each sentence will be repeated twice. When this is heard destroy all code papers, etc. This is as yet to be a completely secret arrangement.

"Forward as urgent intelligence." [1] East wind rain. [2] North wind cloudy. [3] West wind clear.

"From: Tokyo "To: Washington "19 November 1941 "Circular #2354

"When our diplomatic relations are becoming dangerous, we will add the following at the beginning and end of our general intelligence broadcasts:

"(1) If it is Japan-U. S. Relations, "HIGASHI" "(2) Japan-Russia relations, "KITA" "(3) Japan-British relations (including Thai, Malaya, and N. E. I.), "NISHI".

"The above will be repeated five times and included at beginning and end.

"Relay to Rio de Janeiro, Buenos Aires, Mexico City, San Francisco."

These intercepts were confirmed by a dispatch from the commander in chief of the Asiatic Fleet to the Office of Naval Operations dated November 28, 1941; [180] a message directed to the State Department from its diplomatic representative in Batavia dated December 4, 1941; [181] and a dispatch from the Army's military representative in Batavia, reading as follows: [182]

"Japan will notify her consuls of war decision in her foreign broadcasts as weather report at end. East wind rain, United States. North wind cloudy, Russia. West wind clear, England with attack on Thailand, Malay and Dutch East Indies. Will be repeated twice or may use compass directions only. In this case words will be introduced five times in general text."

The foregoing message was sent "deferred" by naval communications for General Miles of the War Department and was not decoded until the morning of December 5, 1941.

Both the War and Navy Departments extended themselves in an effort to monitor for a message in execution of the winds code. Exten-

[177] A detailed record study of the winds code will be found set forth as Appendix E to this report. [178] The circular dispatches were designed for Japanese diplomatic establishments generally. [179] Committee exhibit No. 1, pp. 154, 155. [180] Id,, No. 142. [181] Id. [182] Id.

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sive evidence has been taken concerning the matter, the preponderate weight of which indicates that no genuine execute message was intercepted by or received in the War and Navy Departments prior to the attack on Pearl Harbor. Investigation conducted in Japan strongly indicates no execute message was dispatched before the attack and the British and Dutch, who were also monitoring for an execute message, have advised that no such message was intercepted. [183] A reasonable construction of the code is that it was designed for use in the event ordinary commercial channels of communication were no longer available to Japan, a contemplation which did not materialize prior to Pearl Harbor. The fact that a message "West wind clear," applying to England, was broadcast after the attack tends to confirm this conclusion. [184] Inasmuch as the question of the winds code has been one of the few disputed factual issues in the Pearl Harbor case, there has been set forth in Appendix E to this report a detailed study of the matter.

*Based on the evidence it is concluded that no genuine "winds" message in execution of the code and applying to the United States was received by the War or Navy Departments prior to the attack on December 7, 1941*. It appears, however, that messages were received which were initially thought possibly to be in execution of the code but were determined not to be execute messages.

Granting for purposes of discussion that a genuine execute message applying to the winds code was intercepted before December 7, we believe that such fact would have added nothing to what was already known concerning the critical character of our relations with the Empire of

"HIDDEN WORD" CODE

In addition to the winds code the Japanese in a dispatch on November 27 established another emergency system of communications that has been familiarly referred to as the "hidden word" code. [185] The dispatch establishing this code, which was sent as a circular to all diplomatic establishments, stated: "With international relations becoming more strained, the following system of dispatches, using INGO DENPO (hidden word, or misleading language telegrams) is placed in effect" and further "in order to distinguish these cables from others, the English word STOP will be added at the end as an indicator." Thereafter, a number of code words, apparently arbitrarily chosen, were set forth with the meaning of each word placed opposite thereto. Among the code words were: HATTORI meaning "Relations between Japan and * * * (blank) are not in accordance with expectation"; KOYANAGI meaning "England"; and MINAMI meaning "U. S. A."

On the morning of December 7 a circular telegram from Tokyo was intercepted reading: [186]

"URGENT 92494 *KOYANAGI* RIJIYORI SEIRINOTUGOO ARUNITUKI *HATTORI MINAMI* KINENBUNKO SETURITU KIKINO KYOKAINGAKU SIKYUU DENPOO ARITASS STOP--TOGO.

[183] Id. [184] Id. [185] Committee exhibit No. 1, pp. 186-188. The original code was supplemented by a dispatch of December 2 from from Tokyo to Singapore which was translated after the attack. Committee exhibit No. 1, pp. 216-219. [186] Committee exhibit No. 142-B.

PEARL HARBOR ATTACK 193

The translation as made by the Navy of the foregoing hidden-word message was distributed in Washington to authorized recipients of, Magic at 11 a. m. on December 7 in the following form: [187]

"Relations between Japan and England are not in accordance with expectation."

This was not the complete message, which should have been translated: "Relations between Japan and the following countries are not in accordance with expectation: England, United States." [188] The reason for the message having been distributed on the morning December 7 with the words *United States* omitted is explained by the fact that Captain Kramer in his haste occasioned by the necessity delivering other messages, including the "one o'clock message" overlooked the code word relating to the United States and translated the message as meaning only that "relations between Japan and England are not in accordance with expectation." He indicated that later discovered the error and telephoned at "a quarter of one or 1 o'clock" the correction to his superior and an officer of Military Intelligence. [189]

It is clear that the hidden-word message as literally translated [190] contained no information of any import not already greatly overshadowed, as will hereinafter appear, by other intelligence available on the morning of December 7 even had the words *United States* been included at the time of distribution.

THE "DEADLINE MESSAGES"

The following message, No. 736, from Tokyo to the Japanese Embassy in Washington, relating to the then current Japanese United States negotiations, was intercepted on November 5, 1941: [191]

"Because of various circumstances, *it is absolutely necessary that all arrangements for the signing of this agreement be completed by the 25th of this month*. I realize that this is a difficult order, but under the circumstances it is an unavoidable one. Please understand this thoroughly and tackle the problem of saving the Japanese-U. S. Relations from falling into a chaotic condition. Do so with great determination and with unstinted effort, I beg of you.

"This information is to be kept strictly to yourself only."

On November 11, 1941 another message from Tokyo to Washington, o. 762, was intercepted, referring to the deadline set in the message November 5: [192]

"Judging from the progress of the conversations, there seem to be indications at the United States is still not fully aware of the exceedingly criticalness of the situation here. *The fact remains that the date set forth in my message #736** is absolutely immovable under present conditions. It is a definite dead line and therefore is essential that a settlement be reached by about that time*. The session of Parliament opens on the 15th (work will start on [the following day?]) according to the schedule. The government must have a clear picture of things to come, in presenting its case at the session. You can see, therefore, that the situation is nearing climax, and that time is indeed becoming short.

"I appreciate the fact that you are making strenuous efforts, but in view of the above mentioned situation, will you redouble them. When talking to the Secretary State and others, drive the points home to them. Do everything in your power

[188] The Army translation of the message supplied in March 1944 read as follows "Relations between Japan and ------- are approaching a crisis (on the verge of danger): England, United States." Committee exhibit No. 142-B. [189] Hewitt Inquiry record, pp. 133-136. [190] Id, at pp. 579-581. [191] Committee exhibit No. 1, p. 100. [192] Id., at pp. 116, 117.

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to get a clear picture of the U. S. attitude in the minimum amount of time. *At the same time do everything in your power to have them give their speedy approval to our final proposal*.

"We would appreciate being advised of your opinion on whether or not they will accept our final proposal A."

The deadline was again referred to in a dispatch of November 15 from Tokyo to Washington, stating: [193]

"It is true that the United States may try to say that since we made no particular mention of the changed status of the talks, they were under the impression that they were still of a preliminary nature.

"Whatever the case may be, *the fact remains that the date set forth in my message #736 is an absolutely immovable one*. Please, therefore, make the United States see the light, so as to make possible the signing of the agreement by that date."

Referring to a dispatch from its Washington Ambassador, the following message from Tokyo was intercepted on November 16: [194]

"I have read your #1090, [195] and you may be sure that you have all my gratitude for the efforts you have put forth, but *the fate of our Empire hangs by the slender thread of a few days*, so please fight harder than you ever did before.

"What you say in the last paragraph of your message is, of course, so and I have given it already the fullest consideration, but I have only to refer you to the fundamental policy laid down in my #725. [196] Will you please try to realize what that means. In your opinion we ought to wait and see what turn the war takes and remain patient. However, I am awfully sorry to say that the situation renders this out of the question. I set the dead line for the solution of these negotiations in my #736, and there will be no change. Please try to understand that. You see how short the time is; therefore, do not allow the United States to sidetrack us and delay the negotiations any further. Press them for a solution on the basis of our proposals, and do your best to bring about an immediate solution."

Responding to requests of its Ambassadors, [197] in an intercepted message of November 22, 1941, Tokyo extended the deadline date from November 25 to November 29 in the following terms: [198]

"To both you Ambassadors.

"It is awfully hard for us to consider changing the date we set in my #736. You should know this, however, I know you are working hard. Stick to our fixed policy and do your very best. Spare no efforts and try to bring about the solution we desire. There are reasons beyond your ability to guess why we wanted to settle Japanese-American relations by the 25th, but if within the next three or four days you can finish your conversations with the Americans; *if the signing can be completed by the 29th*, (let me write it out for you--twenty-ninth); if the pertinent notes can be exchanged; if we can get an understanding with Great Britain and the Netherlands; and in short if everything can be finished, *we have decided to wait until that date*. This time we mean it, that the dead line absolutely cannot be changed. *After that things are automatically going to happen*. Please take this into your careful consideration and work harder than you ever have before. This for the present, is for the information of you two Ambassadors alone."

As a follow-up to the foregoing message, Tokyo on November 24, 1941, advised its Ambassadors that the time limit set in the message of November 22 was in Tokyo time. [199]

It is clear from the foregoing messages that "things are automatically going to happen" after November 29, Tokyo time. It is equally clear from information now available that the happening was to be the contemplated departure of the Japanese task force to attack

[193] Id., at p. 130. [194] Id., at pp. 137, 138. [195] See committee exhibit No. 1, pp. 127-129. [196] Id., at pp. 92-94. [197] Id., at p, 159. [198] Id., at p. 165. [199] Id., at p. 173.

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Pearl Harbor. But the question is not what the deadline messages are en now to mean but what they reasonably conveyed to officials in Washington in the days before December 7.

Tokyo had indicated the extreme importance of time as the dead line approached: [200] "The fate of our Empire hangs by the slender thread of a few days." But does this importance and the fact of the deadline indicate an attack at Pearl Harbor or, for that matter, an attack on the United States elsewhere? It must be recalled that on August 17, following the Atlantic Conference, President Roosevelt advised the Government of Japan that if she took any further steps in pursuance of a program of domination by force or threat of force of neighboring countries, the Government of the United States would be compelled to take any and all steps necessary toward insuring the security of the United States. [201] It is not unreasonable to conclude that, failing to secure a satisfaction of her demands by November 29, Japan had determined to launch a program of aggression which she felt would involve her in war against the United States. The extensive employment of her forces to the south after November 29, it would reasonably appear, was regarded as the action to be taken upon expiration of the deadline date. Washington had expressed this estimate to Admiral Kimmel on November 27: [202]

"The number and equipment of Japanese troops and the organization of naval task forces indicates an amphibious expedition against either the Philippines, Thai, or Kra Peninsula or possibly Borneo."

One of the factors considered in dispatching the "war warning" to Admiral Kimmel on November 27 was that of alerting the Fleet before the cut-off date of November 29. [203] We believe that the dispatch of November 27 to Admiral Kimmel beginning, "This dispatch is to be considered a war warning" and the dispatch to General Short of the same date advising that "hostile action possible at any moment" was the equivalent of and in fact was of greater significance than the so-called "deadline messages" merely informing that things would automatically happen after November 29.

Based on what is now known concerning the plan of the Japanese attack, it is believed that in contemplation of the future intelligence such as the deadline messages could well be supplied field commanders as an item of information for their assistance along with dispatches designed to alert and to supply them with an estimate of the situation.