When in deep concentration, Kuroshima generally clasped long, lean fingers over his high, bald skull as if to keep any elusive thought from escaping. On this humid day in early August, he captured a very practical idea: The Navy should hold its annual war games in September instead of waiting for late November and early December. Above all, the games should include study of the Pearl Harbor project in a special room with access only to those directly involved.
Yamamoto took little persuading. Even before the midsummer freeze he had begun to worry lest the customary date might be too late to hold the war games.1 If he waited until then to deal with all the problems which inevitably turned up during these sessions, winter would seize Japan and the Pacific in its icy fist, seriously hampering operations. He realized, too, that this was the logical moment to broach the Pearl Harbor plan once more to the Naval General Staff, now that the presence of land-based aircraft in Indochina somewhat lessened the need for carrier-borne planes in the Southern Operation.
It so happened that at this same time the Naval General Staff had asked the Combined Fleet to send someone to Tokyo because the Navy and Army General Staffs were preparing plans in case of war with the United States and Britain. This offered Yamamoto a double opportunity. “As the relations between the United States and Japan became worse,” he said to Kuroshima thoughtfully, “it is all the more necessary to study the Pearl Harbor plan and to urge the Naval General Staff to accept it.”2
Yamamoto considered the existing Naval General Staff plan inadequate for war against the American, British, Chinese, and Dutch (ABCD) powers, especially against the United States. A study of the southern strategy along with his Pearl Harbor operation at the annual war games would give Nagano and others in his organization a chance to reconsider the latter for inclusion in the overall planning. It would also provide the operational units of the Hawaii air strike force an opportunity to visualize their mission and the problems involved. So once more Yamamoto dispatched Kuroshima to Tokyo to exercise his powers of persuasion on the higher echelon.3
Kuroshima arrived at Naval General Staff Headquarters on August 7 to discuss the “Pearl Harbor air strike and operations against the Philippines and Russia”; he brought with him Arima, Yamamoto’s torpedo and submarine officer.4 Kuroshima conferred long and seriously with Tomioka and members of his Operations Section. He explained that since the embargoes Yamamoto was all the more determined to strike a sudden initial blow against the U.S. Pacific Fleet.
He asked that the Naval General Staff agree to hold the annual war games in September, thus giving Yamamoto plenty of time to study any questions which might arise. He also asked Tomioka to arrange for rooms and equipment in the Naval War College, including a special room to house the Pearl Harbor exercise. He further requested that Tomioka’s office provide all the information necessary on the U.S. Pacific Fleet, the number of American planes, and anything else required for realistic war games. Tomioka agreed to move up the date for the table maneuvers. Accordingly the Naval General Staff set aside the second week in September for the purpose.
But incorporating Yamamoto’s Pearl Harbor plan into Japan’s grand strategy was another matter. Once more Tomioka trotted out the outline he had shown Kuroshima in early spring—the time-honored naval Armageddon following submarine attrition of American warships. Kuroshima read it carefully, but he still considered it “old-fashioned and inadequate.” Then he seized the opportunity to clarify the position of the Combined Fleet.
“As the situation between the United States and Japan is getting serious, an agreement between the Army and Navy is indispensable,” he acknowledged. “But the most important thing under consideration in the Combined Fleet is a plan of operations to defeat the U.S. Fleet at the outset of the war. The Combined Fleet therefore urges the Naval General Staff to study the problem of an attack on Pearl Harbor more seriously.”5
At this point the two men settled down to examine their respective views. Tomioka ticked off the Naval General Staff’s objections with the inexorable logic of a computer.
The success of the operation depended upon surprise, and he did not see how secrecy could be maintained. Such a large force moving so far across the Pacific might conceivably “meet enemy ships or aircraft or ships of neutral countries on the way.” Even if the Americans did not thus uncover the plot, most likely they would do so before the actual strike because of “cautious measures like careful aerial reconnaissance.” In that case Japan would lose the initiative and suffer heavy casualties. Then, too, fighting might break out elsewhere before X-Day and alert the Americans on Oahu.6
Most of the ships would require refueling en route, and the techniques remained to be perfected. The plan might well “collapse in the ocean because of fuel supply,” Tomioka stressed. Nor did the Japanese have any guarantee of finding Kimmel’s ships in port if they did reach the target area, and they would not have sufficient scouting forces to search for the enemy. In addition, the U.S. Pacific Fleet at sea might find and attack the task force in coordination with land-based aircraft. Still another imponderable was the weather, which might force Nagumo to cancel the air raid. “But even in this case,” Tomioka emphasized, “it would be impossible to delay the opening of the war.” And with the beginning of hostilities Oahu and the Pacific Fleet would go on an immediate war footing.7
Even if everything worked out perfectly up to the moment of attack, Tomioka did not expect “sufficient achievement out of the air strike itself.” Once again he listed the factors militating against successful results and set them against the undoubted risks: the shallow water and lack of maneuvering space in Pearl Harbor; probable antitorpedo nets; poor accuracy of horizontal bombing; and ineffective dive bombing. Finally, since land-based air power was both too little and too short-ranged to handle the Southern Operation alone, Japan could not really spare carriers from this area.8
“In summary,” Tomioka concluded, “this Hawaii Operation is speculative and has little chance for success. In the worse case we may even lose our forces which are like tiger cubs now. . . . And . . . we may not only stumble in the Southern Operation, but also have the advance of our task force detected while the diplomatic relationship is still tense, thus becoming a decisive factor in the negotiations.” As for Yamamoto’s chief argument—the need to block the U.S. Pacific Fleet from a flank attack on Japan’s forces going south—Tomioka pointed out that the Americans might instead hit the Marshalls, an attack which would not be “a disadvantageous move from the long-term point of view since we can easily prepare and intercept the enemy . . . when he comes west.”9 Having thus considered every possible eventuality short of the First Air Fleet’s being sunk by a meteor shower, Tomioka rested his case.
Kuroshima then gave the other side of the picture. Tomioka had presented him with no arguments that he was not prepared to refute, though perhaps with more enthusiasm than clear-cut reason. He acknowledged the overriding importance of secrecy but added, “Since there will be appropriate measures for secrecy, we should not worry about it so much.” He admitted that the project involved “various unpredictable factors” and therefore was “an adventurous operation,” but, he emphasized, “war always involves risk and we cannot wage war and be afraid of taking chances.”
Kuroshima insisted that while the invasion of Southeast Asia might go more smoothly with carriers than without, still “it should not be too difficult to carry out the operation with land-based air forces and army air forces. . . .” He stressed that “we should consider the Southern Operation as a part of the entire war against the United States instead of as an independent operation.” For this reason, the Combined Fleet must “first strike a damaging blow against the American Pacific Fleet which controls the Hawaiian area. . . . If we allow the enemy fleet to take the Marshalls and permit them to prepare many flying boats, our recapture of these islands will be difficult and the areas of the southern Pacific will be taken one after the other.”
After further arguments on both sides the match ended in a draw, each agreeing to reexamine his own plan in the light of the other’s.10 To the dispassionate eye, Tomioka appears to have had much the better of the discussion. However, Kuroshima held one potent, if unplayed, trump: Vox Kuroshima, vox Yamamoto, as Tomioka well knew.
Even so, on August 7, 1941, the Naval General Staff had another opportunity to abort Yamamoto’s project. Kuroshima had offered the First Bureau an excellent chance to take the problem directly to Nagano and secure his absolute veto. Yet despite its opposition to Yamamoto’s risky undertaking, it did not do so.
Aboard Nagato, Yamamoto continued to think seriously about attacking Pearl Harbor. Indeed, on August 10, while his flagship rode at anchor in Saeki Bay, he told his Eta Jima classmate Admiral Zengo Yoshida about his plan. Another of Japan’s most distinguished admirals, Yoshida had been Commander in Chief of the Combined Fleet before Yamamoto and had subsequently served as navy minister in three successive Cabinets. He was now a member of the Supreme War Council, a small, select advisory group of admirals who had little, if anything, to do with operations. Yoshida had come to discuss the general political and military situation with his close friend.
“Japan must deal the U.S. Navy a fatal blow at the outset of war,” Yamamoto said. “It is the only way she can fight with any reasonable prospect of success. The Pearl Harbor attack is necessary to give Japan a free hand in the Southern Operation.” Then, distressed that his apprehensions about a conflict with the United States seemed to be taking concrete shape, he added unhappily, “I cannot help feeling that the authorities in Tokyo think war is unavoidable.” As usual, Yamamoto emphasized the absolute secrecy of his plan.
This was the first time Yoshida had heard of the daring design. Being a cautious, practical admiral of the old school, he embodied his immediate reaction in a question: “How will it be possible to send a task force so far from Japan with the present radius of action of the Fleet?”
Yamamoto knew that Yoshida had put his finger on one of the principal difficulties. “The task force will refuel at sea,” he answered. “Training in refueling is now going on. Prospects are favorable for its success.”11
With Yoshida’s inclusion in the Pearl Harbor fraternity, the circle of those in the know continued to widen and would do so increasingly.
At this point there again appears one of those curious circumstances which seem to suggest a stream of thought flowing between Washington and Tokyo, Oahu and Japan. At the very time when the Japanese Navy was improving the means and techniques for attacking Kimmel’s ships, and Yamamoto was securing permission to bring forward the date of the war games in anticipation of initiating the Pearl Harbor strike, the Hawaiian Air Force was preparing a staff study aimed at preventing just such an operation.
On July 10 Colonel William E. Farthing, the six-foot Texan who commanded the Fifth Bombardment Group at Hickam Field, had completed a survey for the Eighteenth Bombardment Wing. This document analyzed “the mission of bombardment aviation in the defense of Oahu” and was in some ways as startlingly prophetic as the Martin-Bellinger Report.12 The ink was scarcely dry on Farthing’s signature when, on July 17, the War Department asked the Hawaiian Department to prepare a study of “the air situation in Hawaii.”13 Because Farthing had already delved into the problem and was an experienced airman, Martin turned the request over to him for action.
The colonel went to work with a will. Major Elmer Rose, his A-4 (Supply), and Captain L. C. Coddington, his A-3 (Operations), assisted him.14 They leaned heavily on Farthing’s original study and gathered all the information available to them on Oahu. They labored hard and imaginatively for about a month. At the end of that period they submitted a detailed, penetrating document of almost 10,000 words.
Not until August 20 did the report, headed “Plan for the Employment of Bombardment Aviation in the Defense of Oahu,” go forward to Washington. Martin sent it through Short to Arnold’s headquarters as an enclosure to a letter under the subject “Study of the Air Situation in Hawaii.” In the last paragraph of the covering letter Martin agreed that by strengthening the Hawaiian Air Force “a positive defense of the Hawaiian Islands can be assured without any assistance from the naval forces giving the Navy complete freedom of action.”15
The Farthing Report, as we shall call it for the sake of brevity, opened:
The key to this plan is found in the provision for first, a complete and thorough search of the Hawaiian area daily during daylight; secondly, an attack force available on call to hit a known objective located as a result of the search and thirdly, if the objective is a carrier, to hit it the day before it could steam to a position offshore of Oahu where it could launch its planes for an attack.16
These would be good tricks if Martin could bring them off.
The report reiterated the Army’s mission: “To defend the Naval Base of Oahu.” It further pointed out that “to perform its missions, the Fleet must have freedom of action without responsibility for the defense of its base.”17
Three “Assumptions” carry unusual interest. “The Hawaiian Air Force is primarily concerned with the destruction of hostile carriers in this vicinity before they approach within range of Oahu where they can launch their bombardment aircraft for a raid or an attack on Oahu.”18 Here the report acknowledged a fundamental tenet of air power: Once an aerial force reached striking distance, it could do enough damage to make the effort worthwhile, provided the attackers were willing to pay the price. Therefore, the Hawaiian Air Force hoped to smash the attempt before enemy aircraft could take off.
Farthing and his officers further assumed: “An enemy will not venture an attack against the Hawaiian Islands until control of the sea lanes of communication is obtained. Then as the enemy fleet approaches these islands, raids by surface vessels, submarine and carrier-based aircraft, may be expected.”19 They slipped up here, as others had done before them. They worked on the principles that an attack would not come until after the beginning of war, that the U.S. Pacific Fleet would not be around to dispute the passage, and that the attack would aim primarily at the Islands as such.
When they got down to tactics, however, their touch grew much surer. Their third assumption began: “Our most likely enemy, Orange, can probably employ a maximum of 6 carriers against Oahu.”20 Whang in the bull’s-eye! Inasmuch as the entire United States Navy could muster only six flattops, it required a bold leap of the imagination to picture Japan’s dispatching a sextet of carriers on a transoceanic Hawaiian raid. In fact, the Farthing-Rose-Coddington creative strategy ran ahead of much Japanese thinking. The First Air Fleet had to fight hard for permission to use the six which actually participated.
Section IV of the report, “Discussion,” dealt exhaustively with many facets of Hawaii’s bombardment aircraft problems and contained a few items of considerable historical interest. For instance, under “The Search,” we find this accurate and uncomfortable statement: “The only manner in which the Hawaiian area can be thoroughly searched for enemy surface craft, particularly carriers . . . is to provide a sufficient number of aircraft to conduct a daily search of the desired area during daylight hours with 100% coverage through 360°.”21 Few would quarrel with the good sense of this assertion, but one can picture Martin thoughtfully shaking his gray head over it. Where were these planes to come from? Even with enough of them, air search would be affected by the human factor, by cloud cover and visibility.
Part 2 of Section IV contained some remarkably successful efforts to second-guess the Japanese: “An enemy should be primarily interested in obtaining the maximum cover of darkness for his carrier approach. . . . The early morning attack is, therefore, the best plan of action to the enemy [Farthing’s italics].”22
The report continued with some clever assessments. “The enemy will be more concerned with delivering a successful attack than he will be with escaping after the attack. He will have carefully considered the cost of the enterprise, will probably make a determined attack with maximum force and will willingly accept his losses if his attack is successful.”23 Neither Yamamoto nor Genda could have expressed the point better.
Farthing emphasized that the enemy “will not have unlimited avenues of approach for his attack” and “must avoid the shipping lanes to negate detection.”24 This factor loomed large in choosing the task force’s route to Hawaii; indeed, Japanese Intelligence worked out an elaborate screen to ensure the minimum chance of detection. Farthing and his officers estimated: “It seems that his most probable avenue of approach is the hemisphere from 0° counter-clockwise to 180° around Oahu. . . .”25 In other words, the Japanese would strike anywhere between north and south from a westerly direction.
“Based on sic the worst situation that could arise, i.e., the employment of 6 enemy carriers against Oahu simultaneously each approaching on a different course,” the report concluded, “an attack force of 36 B-17D’s would be required to disable or destroy the carriers.”26 No one on Nagumo’s staff had any intention of dispersing the carriers to converge on Oahu from six different directions, which would have disrupted the task force, multiplied almost every problem by six, and flown in the face of Gendaism. The six carriers would approach in a body. Nevertheless, there was something to be said for Farthing’s postulating a diversified approach. By keeping their flattops together, the Japanese ran the risk that discovery of one would mean the discovery of all, as occurred at Midway. But Genda and his airmen were willing to take the chance to achieve concentrated air power.
Farthing and his assistants really hit their stride in Section VI, “Recommendations.” First, they asked that “the War Department give immediate consideration to the allotment of 180 B-17D type airplanes or other four-engine bombers with equal or better performance and operating range and 36 long-range torpedo-carrying medium bombers to the Hawaiian Air Force. . . .”27 This was a stunning order for 1941.
To back this up, the report declared:
The sole purpose of the existence of the military establishment on Oahu, ground and air, is for the defense of Oahu as an outlying naval base. The best defense is an aggressive and well-organized offense. . . . We have had clearly demonstrated to us in Europe the fallacy of depending upon passive measures of defense. . . . We must ferret out the enemy and destroy him before he can take action to destroy us.28
Here again the planners thought in terms of a war already declared.
It has been said, and it is a popular belief, that Hawaii is the strongest outlying naval base in the world and could, therefore, withstand indefinitely attacks and attempted invasions. Plans based on such convictions are inherently weak and tend to create a false sense of security with the consequent unpreparedness for offensive action.
These modern Paul Reveres sounded another alarm: “With the United States living and working under a condition of unlimited National Emergency, Japan making its southward movement and the world in general in a complete state of turmoil we must be prepared for D Day at any time.” They ended with an urgent plea:
It is believed that a force of 180 four-motored aircraft with 36 long-range torpedo airplanes is a small force when compared with the importance of this outpost. This force can be provided at less cost to the Government than the cost of one modern battleship. It is further believed that this force should be made available as soon as possible even at the expense of other units on the Mainland.29
The Army Pearl Harbor Board called Farthing’s effort “prophetic in its accuracy and uncanny in its analysis of the enemy’s intention.”30* It was both of these, and could it have been fulfilled, it would have taken from the Navy’s shoulders a burden it should never have been called upon to assume. A 360-degree search might well have discovered Nagumo’s task force and changed history. Unfortunately, however “prophetic,” even “uncanny” the Farthing Report, it was not practical. According to Arnold, in August the entire U.S. Army had only 109 B-17s.31 And these had been heavily committed to mainland defense, Britain, and the Philippines.
The main flaw in the Farthing Report was that which marred all the interservice agreements reached on Oahu and which looked so good on paper. It postulated that war would have begun, giving the Army and Navy time to move into high gear, before the attack would be attempted. Marshall had fallen into this same trap; so had Short in his maneuvers.
One notes the fundamental difference between the American and Japanese planning in connection with the defense and attack, respectively, of the U.S. Pacific Fleet at Pearl Harbor. In theory the American plans could scarcely have been improved. They were clear-cut, farsighted, almost inspired, and revealed a solid understanding of the tactics which the Japanese would conduct on December 7. But these studies lacked substance because they depended for their implementation upon aircraft which the United States did not have in sufficient quantity.
They also lacked the psychological impetus which only a genuine belief can impart. The fact is, however frequently the defenders of Oahu expressed in writing their acceptance of the possibility of a Japanese attack, they considered it improbable. And that included Farthing himself. “I didn’t think they could do it. I didn’t think they had that ability,” he later testified.32
In contrast, the Japanese plan appeared fantastic, an inadmissible risk, almost suicidal, justifying every one of the objections which Tomioka had presented so clearly to Kuroshima. Yet the task force carried it out because such men as Yamamoto, Genda, and many others breathed life into it by their dynamic faith. They counted on aircraft and ships either in existence or soon to be, and where they lacked weapons or techniques, they created them. Theirs was a triumph of spirit over matter, yes, even over intellect.