SECNAV Knox was sent to Pearl Harbor on December 8 1941 to report on the aftermath of the attack. The United States was at war and questions such as what happened, how—and why needed investigation. In the paternalistic view of the United States, the Japanese were not able to execute such an operation unique in its size and scope in naval aviation. It was beyond the means of the United States in 1941, so civilian and military leaders did not see the possibility of such an attack from the Japanese. The SECNAV’s investigation was the first of nine that were held from 1941—1946. Five of the nine stand out and are discussed here. The other four are referred to, to provide context.



Knox completed his report in six days, and submitted it to President Roosevelt on December 14, 1941. It outlined the state of unreadiness of both Army and Navy forces in Hawaii. Knox stated:

There was no attempt by either Admiral Kimmel or General Short to alibi the lack of a state of readiness for the air attack. Both admitted they did not expect it and had taken no adequate measures to meet one if it came. Both Kimmel and Short evidently regarded an air attack as extremely unlikely because of the great distance, which the Japs would have to travel to make the attack and the consequent exposure of such a task force to the superior gun power of the American fleet. Neither the Army nor the Navy Commander expected that an attack would be made by the Japanese while negotiations were still proceeding in Washington. Both felt that if any surprise attack was attempted it would be made in the Far East. 32

Until November 27, 1941, Admiral Kimmel knew that talks with the Japanese were on going, and intelligence in the form of Magic that Admiral Kimmel did get from Washington did not point to Pearl Harbor as a possible area of attack by Japan. The war-warning message did not list Hawaii at all. Kimmel carried out the tasks as assigned to his command under war plans given the shortages of trained men and material in Hawaii to the best of his ability. Those shortages were known to CNO Admiral Stark and SECNAV Knox and the President. Admiral Kimmel was relieved of command on December 16, 1941. 33


Roberts Commission

Owen J Roberts

Four days after Knox submitted his report to the President, Roosevelt called into being the Roberts Commission to investigate and report the facts relating to the attack made by Japanese armed forces upon Pearl Harbor in the territory of Hawaii on December 7, 1941. After nearly six weeks of investigation, on January 23, 1942 the Commission submitted its report to Roosevelt. Among the report’s stranger findings are the following:

13. There were deficiencies in personnel, weapons, equipment, and facilities to maintain all the defenses on a war footing for extended periods of time. But these deficiencies should not have affected the decision of the responsible commanders as to the state of readiness to be prescribed. 34

The above statement was and is wrong in that shortages as listed above had to affect decisions made by Kimmel. If, for example, he had the number of planes required to carry out search operations according to war plans Kimmel would have done so. Instead, because of the shortages, he had to make adjustments based on the personnel, weapons, and equipment available. Adjustments meant there would be possible gaps in readiness.

The report also states:

17. In the light of the warnings and directions to take appropriate action, transmitted to both commanders between November 27 and December 7, and the obligation under the system of coordination then in effect for joint cooperative action on their part, it was a dereliction of duty on the part of each of them not to consult and confer with the other respecting the meaning and intent of the warnings, and the appropriate measures of defense required by the imminence of hostilities. The attitude of each, that he was not required to inform him. 35

This judgment was and is also wrong. Kimmel and Short did, in fact, consult and confer with each other respecting the meaning and intent of the warnings, and the appropriate measures of defense required by the imminence of hostilities. According to Admiral Kimmel:

My relations with General Short, which were once the subject of considerable confusion in the public mind, have now been clarified by exhaustive investigations. I need not labor it. It has been established that our official and social relations were friendly, that we frequently conferred on official matters of common interest and invariably did so when either of us received messages which had any bearing on the development of the United States-Japanese situation, or on our several plans in preparing for war. 36

Thus, the charge of dereliction of duty was baseless. It should have been clear to the Roberts Commission that Admiral Kimmel did all that he could. More than likely, it is a function of time that caused the Roberts Commission to conclude what they did. Kimmel did testify before the Commission, and either was not questioned about his relations with General Short, or his testimony was discounted and rejected. In any case, the investigation of the Roberts Commission was undertaken too soon after the attack to be objective and have all important information made available to them.


Hart Inquiry

Two years after the Roberts Commission’s findings were published SECNAV Knox directed Admiral Thomas C. Hart, US Navy, Retired to Examine witnesses for the purpose of recording and preserving testimony pertinent to the Japanese attack on Pearl Harbor in the following letter dated February 12, 1944 :

… Whereas, on 7 December 1941, Japanese armed forces made an attack against Army and Navy installations and ships of the United States Pacific Fleet at Pearl Harbor, Oahu, Territory of Hawaii, which attack was a complete surprise to the commanders of the said installations and ships, and

Whereas, regrettable loss of life and extensive damage resulted from the said attack, and

Whereas, certain members of the naval forces, who have knowledge pertinent to the foregoing matters, are now or soon may be on dangerous assignments at great distances from the United States, and

Whereas, it is now deemed necessary, in order to prevent evidence being lost by death or unavoidable absence of those certain members of the naval forces, that their testimony, pertinent to the aforesaid Japanese attack be recorded and preserved,

I hereby detail you to examine such members of the naval forces thought to have knowledge of facts pertinent to the said surprise attack and fully record the testimony given thereby. Under the authority of Title 5, Section 93, of the U. S. Code, you are authorized and directed to administer an oath to any witness called by you to testify or depose in the course of this examination into the subject-named matter.

In view of the fact that Rear Admiral Husband E. Kimmel; U. S. Navy, Retired, was, on 7 December 1941, serving on active duty as the commander-in-chief, U. S. Pacific Fleet, with the rank of Admiral, U. S. Navy, and [A(2)] therefore, has an interest in the matter into which this examination is being made, you will notify him of the times and places of the meetings to be had and that he has the right to be present, to have counsel, to introduce, examine, and cross-examine witnesses, to introduce matter pertinent to the examination and to testify or declare in his own behalf at his own request.

Upon completion of the examination you will submit a complete record of all the testimony taken, including any documents introduced therein, to the Secretary of the Navy.

The provisions of Sections 733 and 734, Naval Courts and Boards, will govern the proceedings of this examination, in so far as such provisions are applicable thereto.

The necessary clerical assistance to aid you in recording tphe testimony will be furnished you upon your request by the appropriatep command in the area in which meetings are held.


The Hart Inquiry heard testimony from 40 witnesses during a fopur-month period from February 22- June 15, 1944 . Admiral Hart informed Adpmiral Kimmel in a letter dated February 17, 1944:

… In compliance with the portion of reference (a) above quotepd, you are hereby advised that the first meeting of the examinationp will occur at 0930 a. m. on Tuesday, 22 February 1944 in room 2744, Navy Department, Washington, D. C. You have the right to be present at that and supbsequent meetings, to have counsel, to introduce, examine, and cross-examine witnesses, to introduce matter pertinent to the examination and to testify or declare in your own behalf at your own request.38

Kimmel was kept informed throughout the inquiry, but he was concerned as to how his testimony would be used. In correspondence with SECNAV Knox Kimmel concluded that his fate was in the hands of the SECNAV. To Kimmel, the proceedings smacked too much of the Roberts Commission, which had declared him guilty without trial or opportunity to defend himself, and then made a public announcement of its accusatory findings to the nation. 39 Given the conclusions of the Roberts Commission, Kimmel mistrusted the SECNAV’s assurance that the inquiry would be run by the book. Thus, Kimmel chose not to take part in the investigation. 40

The Hart Inquiry reached no findings of fact nor drew any conclusionsp. It simply compiled and put on record testimony. Of the 40 witnesses, pthree stand out Richmond Kelly Turner, William F. Halsey, and L. F. Safford. Both Turner and Halsey testified that Kimmel did not have the men or material in Hawaii to carry out offensive operations. In answer to question , Turner testified in part:

Vice Admiral Richmond Kelly Turner in 1944. In 1941 he was director of Navy war plans
It was realized that Admiral Kimmel did not have at hand all thpe material and men and organizations to proceed immediately with a strong offensive to the Gilberts or the Marshalls. The Navy Department was making every effort to try to set up base materiel and organizations that would permit Admiral Kimmel, in the course of a comparatively short time, to initiate supch an offensive. Admiral Kimmel, whether in writing or orally, I don't recall, expressed the view that he did not have the forces suitable for conducting an offensive in the immediate future. There was no disagreemenpt in the Department with such a view…. 41

Shortages as stated above made the need for full intelligencpe information in Hawaii greater. In answer to the following question:

51. Q. Did you feel, at that time, that all necessary steps were ptaken to apprise the Commander-in-Chief, Pacific Fleet of the apprehensiopn of the Chief of Naval Operations as to a surprise air attack on Oahu ?

Turner testified:

A. There was no specific warning sent out against attack on the Fleet here at the time the war warnings were dispatched. The only measures that we estimated specifically the Japanese would take were the general forms of his major attack, which was on Malay, the Philippines , and possibly Borneo, initially. That is, it was the major movement with which we were concerned in the Department. It was against policy-rightly, so, I believe-to be too specific in details as to tactical matters. The idea was that we would give the Commanders-in-Chief general tasks, provide them with full information, and assign to them forces adequate for executing those tasks. We looked to the officers in the field to decide all tactical matters and methods. We did not wish to hamper them with detailed instructions concerning matters within their own fields of action. This was particularly important in the case of the Pacific and Asiatic Commands, which are so far distant from Washington that the officers there can never be adequately advised as to events and conditions. 42

If the idea was to give Kimmel full information; then why did Turner, who was director of Navy war plans, object to sending the message of September 24, 1941 to Kimmel? The Director of Naval Intelligence Captain Allan G. Kirk thought the message should be sent to Kimmel. Admiral Hart never questioned Turner on the point, and did not call Captain Kirk to testify. Nor did Hart call CNO Stark, who stated to Kimmel that Kimmel would be kept informed. Turner’s objection should have been over ruled by the CNO.

Admiral William F. Halsey Commander of the carrier that launched thpe raid on Tokyo was called by Admiral Hart. In answer to the following question:

Admiral William F. Halsey
54. Q. Sir, did you feel, at that time, that the sum total of thpe Commander-in-Chief's intelligence reports was at all adequate? In other woprds, did you feel that the Commander-in-Chief was fairly well informed asp to what the Japs were doing or did you feel that you were operating ipn the dark there?

Halsey testified:

A. I did not feel that we were well informed on what the Japs wepre doing and I felt that we were operating in the dark. I had the personal feeling, entirely personal, that they knew a lot more in Washington than we knew out there and that we should have been inform. 43

Halsey had the feeling that he and Kimmel were in the dark. He believed Kimmel demanded more information from Washington.

On the point of surprise attack by Japan, Halsey testified in part:

[W]e felt sure that they would pull something like that, but we thought it would take place in the Far East rather than Honolulu, except by submarines, which was the gist of the conversation. We underestimated their ability to operate carriers, or we did not give it enough consideration. 44

Again, the Far East was thought to be the likely target, and Halsey’s statement of underestimation showed the paternalistic view of the Japanese held before the attack.

Captain L. F. Safford

L. F. Safford was the officer in charge of Communication Intelligence in December 1941. Safford testified, in answer to the following:

6. Q. To what special branch of intelligence were the duties of the main station at Pearl Harbor confined?
A. To the dispositions and plans of naval forces in the Pacific Ocean and to surveillance over Japanese naval communications. We expected that this would prevent the Fleet being surprised as the Russians had been at Port Arthur. These duties were prescribed in the current War Plans (WPDNC-8: Appendix IV; Art. 4-25) approved March 1940, and by dispatches and letters of instruction issued by the Chief of Naval Operations. These duties did not include surveillance over Diplomatic communicatipons of any sort. The personnel of this Unit had about four or five years of C. I. experience on the average. The officers included our best, and six or seven had had previous C. I. duty in the Asiatic C. I. Unit. 45

The above were the station’s stated duties. Safford was clear tphat those duties did not include surveillance over diplomatic communicatipons of any sort. Thus, the Pacific Fleet was dependant on ONI for Magic, thatp is, diplomatic intercepts. The Asiatic Fleet, however, had such equipment apnd personnel. Safford testified, in answer to the following:

7. Q. To what special branch of intelligence were the duties of tphe main station at Corregidor confined?
A. The Asiatic Unit was at the disposal of the Commander-in-Chief, U. S. Asiatic Fleet to use as he saw fit. During 1940 and early 1941, this was mostly concerned with Japanese Diplomatic communications, but in October or November, 1941, it shifted its main attention to Japanese Naval communications. The personnel of this Unit had about two or three years of C. I. experience on the average, and the officers were young, enthusiastic, and capable. 46

The Asiatic Fleet was responsible for Japanese diplomatic intercepts, and the Pacific Fleet was given the responsibility for surveillance over Japanese naval communications. How was it, then, that the message of September 24, 1941 was not sent to Kimmel? It was clearly Magic; therefore, outside the ability of the Pearl Harbor station to decode. The Asiatic Fleet had such ability, but did not send the message directly to CINC PAC. Instead, it was sent to ONI in Washington; where the message was not sent top CINC PAC. That was an intelligence failure of the first magnitude. Even if, as it seems likely, the message was misconstrued; it should have been sent to CINC PAC for his information.

Why was the message misconstrued? Because of the overall view of the United States that the Philippines were the most likely Japanese target; duep to their paternalistic underestimation of the Japanese ability to operate carriers. Two days before the Japanese Fleet put to sea, as Safford testified in part:

On November 24, 1941, we learned that November 29, 1941, Tokyop time was definitely the governing date for offensive military operations pof some nature. We interpreted this to mean that large-scale movements for the conquest of Southeast Asia and the Southwest Pacific would begin on that date, because, at that time, Hawaii was out of our minds. 47

Then, eight days later, as Safford testified, on December 7 p1941:

Finally, at 10:15 a.m. (Washington time), December 7, 1941, we received positive information from the Signal Intelligence Service (War Department) that the Japanese declaration of war would be presented to the Secretary of State at 1:00 p. m. (Washington time) that date. 1:00 p. m. Washington time was sunrise in Hawaii and approximately midnight in the Philippines, and this indicated a surprise air raid on Pearl Harbor in about three hours. Kramer appended a note to this effect to the paper sent over from S. I. S. before presenting it to the Secretary of the Navy. I do not know whether or not a copy of this note was appended to the paper given to Admiral Stark. 48

It is unclear just how the above information indicated the attack on Pearl Harbor. If it did and SECNAV had it; how did it not get to Kimmel before the attack? That was another intelligence failure of the first magnitude.


Naval Court of Inquiry

This was the fifth investigation into the attack; held almost at the same time as The Army Peparl Harbor Board, which met from July 20—October 20, 1944. The Naval Cpourt of Inquiry met from July 24—October 19, 1944 The Court did reach findipngs of fact and drew conclusions. The most damning of which was leveled at CNO Stark and stated:

Based on Findings XVIII and XIX, the Court is of the opinion that Admiral Harold R. Stark, U.S.N., Chief of Naval Operations and responsible for the operations of the Fleet, failed to display the sound judgment exppected of him in that he did not transmit to Admiral Kimmel, Commander-in-Chief, Pacific fleet, during the very critical period 26 November to 7 December, important information which he had regarding the Japanese siptuation and, especially, in that, on the morning of 7 December, 1941, he did not transmit immediately the fact that a message had been received which appeared to indicate that a break in diplomatic relations was imminent, and that an attack in the Hawaiian area might be expected soon. 49

The September 24, 1941 message could be added to the above, but pat the time, Magic was still Top Secret, and could not be made public. The Court also concluded that there was a basis for the belief that an attack would come in the Far East.

Based on Finding XVII, the Court is of the opinion that, although the attack of 7 December came as a surprise, there were good grounds for the belief on the part of high officials in the State, War, and Navy Departments, and on the part of the Army and Navy in the Hawaiian area, that hostilities would begin in the Far East rather than elsewhere, and that the same considerations which influenced the sentiment of the authorities in Washington in this respect, support the interpretation which Admiral Kimmel placed upon the war warning message of 27 November, to the effect that this messagpe directed attention away from Pearl Harbor rather than toward it .

Kimmel made judgments based on the information available to him, and according to the Court based on Finding VI:

[T]he deficiencies in personnel and material which existed during 1941, had a direct adverse bearing upon the effectiveness of the defense of Pearl Harbor on and prior to 7 December. 50

That conclusion is the polar opposite of the Roberts Commission, as stated above, on the same point. Even if Kimmel was at full readiness, the Fleet could not, as a matter of law, take any offensive action without being attacked first:

Based on Finding III, the Court is of the opinion that the Constitutional requirement that, prior to a declaration of war by the Congress, no blow may be struck until after a hostile attack has been delivered; prevented the Commander-in-Chief, Pacific Fleet, from taking offensive action as a means of defense in the event of Japanese vessels or planes appearing [in] the Hawaiian area, and that it imposed upon him the responsibility of avoiding taking any action which might be construed as an overt act. 51

Thus, if Kimmel had all the information he should have had the best the Fleet could have done would to have been at sea. Moreover, if planes had spotted the Japanese Fleet; the Pacific Fleet would have suffered losses in any case whether it attacked first or not.


The Joint Congressional Committee

This was the ninth and last investigation into the events surrounding Pearl Harbor . The three that came before The Joint Congressionpal Committee, which met from November 15, 1945—May 23, 1946, are The Clarke Investigation August 4—September 20, 1944, Clausen Investigation January 24-September 12, 1945, and Hewitt Inquiry May 14—July 11, 1945. The findings of all nine investigations are in the pages of The Joint Congressional Committee Report.

The Report itself is divided in two parts Majority and Minority findings. It is the most comprehensive of the fact-finding efforts. The findings of the Committee and associated material alone are about 700,000 words. In all, the Report consists of some twenty-three million words. The Committee’s conclusions support some of the findings of the eight earlier investigations, and reject others. The Majority Report states in Conclusion 8 the following:

Specifically, the Hawaiian commands failed:

(a) To discharge their responsibilities in the light of the warnings received from Washington , other information possessed by them, and the principle of command by mutual cooperation

(b) To integrate and coordinate their facilities for defense and to alert properly the Army and Navy establishments in Hawaii particularly in the light of the warnings and intelligence available to them during the pperiod November 27 to December 7, 1941.

(c) To effect liaison on a basis designed to acquaint each of them with the operations of the other, which was necessary to their joint security, and to exchange fully all significant intelligence

(d) To maintain a more effective reconnaissance within the limits of their equipment.

(e) To effect a state of readiness throughout the Army and Navy establishments designed to meet all possible attacks.

(f) To employ the facilities, materiel, and personnel at their command, which were adequate at least to have greatly minimized the effects of the attack, in repelling the Japanese raiders

(g) To appreciate the significance of intelligence and other inforpmation available to them 52

These conclusions seem to take into account the fact that the Hawaiian commanders did not have all necessary intelligence. Conclusion 11 states in part The Intelligence and War Plans Divisions of the War and Navy Departments failed:

(a) To give careful and thoughtful consideration to the intercepted messages from Tokyo to Honolulu of September 24, November 15, and November 20 (the harbor berthing plan and related dispatches) and to raise a 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 to the Hawaiian commanders for their assistance, along with other information available to them, in making their estimate of the situation.53

The lack of all necessary intelligence led to most of the failurps of the Hawaiian commands. The others have been refuted by Kimmel, Hart Inquiry Testimony, and the conclusions of the Naval Court of Inquiry.

  1. The failure of the Hawaiian commands to discharge their respponsibilities in the light of the warnings received from Wasphington , other information possessed by them, and the principle of command by mutual cooperation. Kimmel refutes this , as does the Naval Court of Inquiry Conclusion 5:
Admiral Kimmel and Lieut. General Short were personal friends. They met frequently, both socially and officially. Their relations were cordial and cooperative in every respect and, in general, this was true as regards their subordinates. They frequently conferred with each other on official matters of common interest, and invariably did so when messages were receivped by either which had any bearing, on the development of the United States-Japanese situation, or on their several plans in preparing for war. Each was mindful of his own responsibility and of the responsibilities vested in the other. Each was informed of measures being undertaken by the other in the defense of the Base to a degree sufficient for all useful purposes. 54
  1. The failure of the Hawaiian commands to maintain a morpe effective reconnaissance within the limits of their equipment. Again, this is refuted, as Kimmel stated:
Search was to be instituted only when there was information from other sources that a carrier strike against the islands was possible within narrow time limits. This was a makeshift none better was possible with the means at hand. 55

Kimmel’s decision found support in the Naval Court of Inquiry Conpclusion 13 stating in part:

The Commander-in-Chief, Pacific Fleet, for definite and sound reasons and after making provision for such reconnaissance in case of emergency, specifically ordered that no routine long-range reconnaissance be undertaken and assumed full responsibility for this action. The omission of this reconnaissance was not due to oversight or neglect. It was the result of a military decision, reached after much deliberation and consultation with experienced officers, and after weighing the information at hand and all the factors involved. 56

More effective reconnaissance within the limits of their equipment rpequired all necessary intelligence, which the Hawaiian commanders did not have. It is unclear how the Hawaiian commanders could have done more within the limits of their equipment.

Conclusion 17 of the Minority Report seems, not only, to question Conclusion 8 of the Majority Report, but also the Germany first strategy:

High authorities in Washington failed to allocate to the Hawaiian commanders the material which the latter often declared to be necessary to defense and often requested, and no requirements of defense or war in the Atlantic did or could excuse these authorities for their failures in this respect. 57

The questioning of the Germany first strategy would seem to clear Kimmel of any major mistakes. It is unclear whether a Japan first strategy would have worked; it did not happen.



32 SECNAV Report, - Pearl Harbor Attack Knox; PHA Part 24: 1753.

33 For a fuller discussion of Kimmel's relief of command, see Keegan Thesis,, 11-14.

34 Report Of The Commission Appointed By The President Of The United States To Investigate And Report The Facts Relating To The Attack Made By Japanese Armed Forces Upon Pearl Harbor In The Territory Of Hawaii On December 7, 1941, accessed July 29, 2015, - Pearl Harbor Attack Roberts Commission, (Hereinafter Roberts Commission); PHA Part 39: 20.

35 Roberts Commission, - Pearl Harbor Attack Roberts Commission; PHA Part 39: 21

36 Kimmel, 9-10.

37 Hart Inquiry Precept for an Examination of Witnesses and the Taking of Testimony Pertinent to the Japanese Attack on Pearl Harbor, Territory of Hawaii, accessed July 30, 2015, - Pearl Harbor Attack - Hart Inquiry ; PHA Part 26: 3-4.

38 Hart Inquiry Exhibit 1, “Letter from Adm. Hart to Adm. Kimmel of February 17, 1944,” accessed July 30, 2015,; PHA Part26: 473.

39 Beach, 119.

40 For an examination of Kimmel's concerns, see Keegan Thesis,, 24-27.

41 Hart Inquiry Testimony Richmond K. Turner, Vice Admiral, USN Monday, April 3, 1944 Twentieth Day, accessed July 30, 2015,, (Hereinafter Turner); PHA Part 26: 265.

42 Turner,; PHA Part 26: 275.

43 Hart Inquiry Testimony William F. Halsey, Jr., Admiral, USN Wednesday, April 12, 1944 Twenty-Sixth Day, accessed July 30, 2015, (Hereinafter Halsey); PHA Part 26: 325.

44 Halsey,; PHA Part 26: 325.

45 Hart Inquiry Testimony L. F. Safford, Captain, USN Saturday, April 29, 1944 Thirty-Second Day, accessed July 31, 2015, (Hereinafter Safford); PHA Part 26: 388.

46 Safford,; PHA Part26: 388.

47 Safford,; PHA Part26: 390.

48 Safford,; PHA Part26: 390.

49 Report of Naval Court of Inquiry October 19, 1944, accessed July 31, 2015, (Hereinafter Naval Court); PHA Part 39: 321.

50 Naval Court,; PHA Part 39:319.

51 Naval Court,; PHA Part 39:318.

52 JCC Report, - Pearl Harbor Attack - Congress ; PHA Part 40: 252.

53 JCC Report, - Pearl Harbor Attack - Congress; PHA Part 40: 252.

54 Naval Court,; PHA Part 39:299.

55 Kimmel, 15.

56 Naval Court,; PHA Part 39:308-309.

57 JCC Report,; PHA Part 40: 543.