Even a superficial study of the vast verbiage dealing with the Japanese attack on Pearl Harbor indicates that the far greater portion of its volume is devoted to a search for American sins of omission and consequent responsibility for the disaster. The errors of commission are obviously few and unimportant. There is a constant reiteration, principally by more or less tacit implication, that if certain steps had been taken, the defeat might have been greatly minimized or entirely averted. This paper proposes to discuss four of the most plausible “ifs,” with a view to expounding what could have been the results had these “might-have-beens” actually affected the Pearl Harbor campaign. It will attempt to do so while avoiding, as far as humanly possible, the initiation of any controversy. Space limitations, alone, will prevent any discussion of events on the high political level, and of diplomacy or grand strategy.
To avoid enmeshment in a profitless squirrel cage of speculation and whirling from minor hypothesis to consequent minor conjecture, it is necessary to assume that definite decisions were made at specific times that an attack on Pearl Harbor was probable as well as possible. Exactly how such decisions could have been reached, or by whom, is immaterial to the purpose of this paper.
Our first “If” assumes that the military establishment of the United States began to act on November 27, 1941, on the premise that the Japanese might attack Pearl Harbor in the near future. Under these circumstances the initial moves of our forces would have been the recall of the Saratoga from the West Coast and the dispatch of patrol plane squadrons to Midway, Johnston, and Palmyra Islands. On the basis of then existing estimates such as the Bellinger-Martin one, and the over-all patrol plane availability, long-range scouting to 700 miles from Midway on the sector north to north-east and station patrols on the Midway-Johnston-Palmyra line would have been the optimum that could have been expected from these outlying units, other than an occasional scout towards the Mandated Islands. Naturally, in view of the actual route taken by the Japanese attack force, this effort would have been wasted except insofar as the negative information so obtained would have enhanced the freedom of movement permitted the U. S. Fleet. The remaining patrol planes with possible reinforcements from San Diego would have supplemented this long-range reconnaissance by similar patrols from Oahu to the northwestward or in advance of our fleet. Their available numbers, even with the maximum possible reinforcements from the West Coast, would not have permitted an optimum coverage of even the most dangerous sectors. The actual daily search plan would have required some very nice decisions involving such factors as holidays in the coverage obtained the previous day of the Midway sector, aircraft availability, and anticipated movements of the fleet.
Assuming that decision and preparation of plans occupied all of November 27th, subsidiary planning and preparations for the patrol plane movements to the outlying bases would have consumed the twenty- eighth. The patrol plane movements could have been effected the following day and the initial scouting from the chosen bases on the last day of November would have permitted a U. S. Fleet sortie on December 1st under the most favorable practicable circumstances on the basis of information then available. Actual movements of the fleet would have been somewhat dependent upon our hypothetically advanced return of the Saratoga to Hawaiian waters. Therefore it appears logical to assume that the fleet would have operated generally to the north and eastward of the Japanese objective, as did the forces of Admirals Spruance and Fletcher under somewhat similar conditions just prior to the battle of Midway. Even had the Saratoga been available on the sortie day, the risk of getting too far from Oahu for interception, had the Japanese taken a route via tire Mandated Islands, would have been too great to have permitted much of a venture to the northwest of Oahu.
Of course, a “station” generally along the Pearl Harbor-Midway line might have facilitated interception regardless of whether the Japanese chose the northern or the southern route. However, such a fleet position would have been disadvantageous in that tactical contact would have probably been made after, instead of before, any attack on Pearl Harbor itself. It must be remembered that in 1941 the fuel storage at Pearl Harbor was relatively vulnerable to aerial attack, and that fleet oilers were far too few in number to have rendered the prospect of loss of the Oahu fuel other than calamitous in a situation where the entire fleet was at sea with depleted bunkers.
Even after the Saratoga had joined the fleet (after refuelling at Pearl Harbor), the officer in command would have been well advised to have remained inside the radius of his Oahu-based patrol planes if only because the Japanese planes of that date materially outranged those with which the Saratoga, Lexington, and Enterprise were then equipped. Of course, we were then not fully aware of that important fact, and this ignorance alone might have resulted in a disaster far greater than the actual Pearl Harbor had our fleet accepted an engagement under the given conditions in an area beyond range of our patrol planes. Put under our present assumptions, and discounting any possible and fortuitous earlier sighting of the Japanese force by one of our submarines, it does not seem likely that the enemy would have been sighted before the afternoon of December 6th even if he had continued on the track actually taken.
And here we must consider the possible effect that the Fleet sortie might have had upon the Japanese plans. Our basic decision might have included steps to stop all flow of information from Oahu to the Japanese. However, such action, even if fully effective, might have been interpreted by the Japanese as a mere reflection of increasingly strained relations. The Japanese plan, as reported after the war, contained provisos as follows: if discovered prior to X-2 day (December 5th), return to Japan; if discovered prior to X-1 day, action optional; if discovered on X-1 or X days (December 6th or 7th), continue and deliver the attack; if interception should be attempted by the American fleet, counter-attack; and if, on arrival in Hawaiian waters, the American fleet was at sea and not in Pearl Harbor, scout on a 300 mile radius around Oahu and attack if contact results, but otherwise withdraw.
With these stipulations in mind it seems plausible under our present hypothesis to assume further that by December 3rd Admiral Nagumo would have had, at best, positive information of the fleet sortie, or, at worst, an absence of all data from Oahu, indicating strongly that a complete surprise could not be confidently anticipated. As the refuelling of his force at sea actually took place on that date it might have been possible, prior to the completion of that critical evolution, for the entire plan to have been cancelled without “loss of face” to those originally advocating the Pearl Harbor attack. On the other hand, as indicated before, effective counter-espionage on Oahu might have been discounted, and the U. S. Fleet sortie—if known at this time—might have been attributed ’ to a mere military reflection of the diplomatic uneasiness. If we can assume that, in Japanese semantics, the “discovered” in the provisos to the Jap plan of attack means “sighted and reported,” then the last stipulation would have governed. An attempted 300 mile circuit of Oahu could hardly have failed to produce a naval battle. Our first “if” therefore boils down to the probability that IF we had decided definitely on November 27th that the Japanese would probably attack Pearl Harbor in the near future, then a naval engagement would have been fought to the northward of Oahu, probably on December 7th.
While the writer makes no pretense to any insight into Japanese psychology, it appears plausible that once the attack force had sailed from Ilitokappu bay, it would have been quite difficult for it to have been recalled by any Japanese volition in the absence of any “discovery” prior to X-2 day or of an American diplomatic surrender. Instead, the inertia affected other forces already set in motion; the inexorable march of events, the Japanese spirit of fatalism, and their subsequently manifested tendency to persist in plans once started—all these would have conspired to produce a game of “buck passing” on the grand scale— Nagano to Yamamoto to Nagumo, or whatever were the effective Jap “channels” at this time. And if the decision had been left to Admiral Nagumo, the fear of “loss of face” alone might have made him decide to continue to Hawaiian waters in the absence of any definite recall by higher authority. If we then conclude that an engagement would have resulted, it is difficult to assume that the American officer in tactical command would have lightly discarded the advantages of remaining within range of his Oahu-based patrol planes.
Assuming Nagumo had kept to his actual track, no contact could have been reasonably expected before the afternoon of December 6th. However, if the Japanese Admiral had been aware of the absence of the U. S. Fleet from Pearl Harbor, he might have altered course to the eastward at sunrise on the 6th to remain beyond patrol plane range while attempting to locale our licet by aerial scouting during that day. With our 17-knot battleships hampering the mobility of our fleet, Admiral Nagumo’s fleet speed of 26 knots would have given him an immense advantage had he been successful in so making contact. In fact, nearly every factor would have favored the Japanese. First of all, they would have had a nearly 2-to-1 advantage in air striking power. In addition, if we except the numerically impotent Hawaiian based Army B-17’s, this aerial force materially outranged ours. Also we must remember that never again during the entire war did a Japanese Admiral have under his command as superbly trained, fresh, and efficient an aerial striking force as the one which raided Pearl Harbor. By contrast, our carrier pilots had not yet achieved the efficiency they reached at Midway and later engagements. Finally, our tactical thinking was then still inclined to consider carrier duels as merely the overture to the engagement of the battle lines.
All in all, if we merely consider what happened at Midway, where many of the initial Japanese advantages had disappeared, and apply the old thumb rule of damage indicted varying inversely as the squares of the fire power engaged, it would be difficult to assume an American victory. (Parenthetically, this rule worked out at Midway, if we disregard non-essentials. The Japanese had four carriers; we had three, plus the equivalent of about one carrier in our shore-based air. But with the enemy devoting one half of his air striking power to the tactically non-essential attack on Midway Island itself, he was left with only the equivalent of two carrier air groups at the scene of the vital part of the engagement—at sea—to oppose our four. Hence the theoretical loss should have been 16 to 4, or four Jap carriers sunk to one of ours which, of course, was the actual result.) Consequently, disregarding chance which might have favored the enemy rather than ourselves, our hypothetical battle might well have resulted in losses based on the results obtained by six carrier air groups opposed to three, or 36 to 9 in favor of the Japanese. On this basis, we might have expected to lose all three of our carriers to one for the Japanese. Had such a disaster taken place, follow-up attacks on our then comparatively defenseless battleships would have undoubtedly produced a defeat far more devastating than did the real Pearl Harbor.
Naturally, in arguing on this basis we are discounting certain moral factors which might have produced quite different results. Knowing our fleet was at sea, Admiral Nagumo might have exercised considerable caution, particularly if his early losses had been as much as the two carriers the Japanese had expected would be lost in the attack on Pearl Harbor. However, the relative weakness of our fleet at this moment in what later proved to be the really effective naval striking power—the air groups of our carriers—would have made the chance of an American victory almost beyond the realm of possibility. And a defeat under such circumstances would have been far worse to morale than was Pearl Harbor. It is bad enough to be defeated by a treacherous surprise attack; it is even worse to be licked when presumably ready to fight. We came up from Pearl Harbor fighting mad; a defeat in this “if” battle might have resulted in a far less favorable reaction.
The second of our “ifs” is concerned with the stoppage of radio intelligence tending to locate the Japanese carriers during the first week of December, 1941. To quote from Admiral King’s comments on the Naval Court of Inquiry, “ . . . up to December 2, no reliable estimate could be made of the whereabouts of four of Japan’s ten carriers, and . . . there was no information as to any of the carriers thereafter.”1 IF, on the basis of this negative information or of any other data, an estimate had been made on December 3rd that an attack on Pearl Harbor was probable in the very near future, the actual disposition of our forces on that date must be considered. The Saratoga was on the West Coast and would be out of the picture entirely. On the morning of the, 4th Admiral Halsey was off Wake Island, launching a squadron of Marine fighters from the Enterprise. Admiral Brown with the Lexington and Task Force 3 (less battleships) was at sea to the south of the Oahu-Midway line. One patrol squadron was at Midway; a second was to depart from Wake for Pearl after extensive scouting while based on Wake to cover the advance and retirement of Task Force 8. Under these conditions a long-range patrol plane reconnaissance as outlined in our November 27th “if” would be indicated, with modifications to give the task forces at sea greater coverage in advance of their movements. In view of the fuel situation in Admiral Halsey’s task force, a rendezvous with Admiral Brown to the eastward of Midway would have been indicated. The battleships were in Pearl Harbor, principally because of a shortage of destroyers to provide them with adequate anti-submarine screens. Consequently it might have been considered advisable to keep them in port on short notice pending more definite indications, although an immediate sortie on the morning of the 4th would have permitted their joining Admirals Halsey and Brown on the Pearl-Wake line early on the morning of December 6th. The difference in this situation and our earlier IF would be that our fleet—this time with only two carriers— would be some 700 miles West of Pearl Harbor. If Pearl Harbor had been reported as empty to Admiral Nagumo, he would probably have started the 300 mile circuit of Oahu. In view of the patrol plane availability which would have precluded our covering of all sectors, if contact had not been made with his force on December 6th, he might well have avoided detection until December 8th. By this time he would have been south of the Hawaiian chain, assuming that he had not in the meantime decided to attack the fuel storage and other permanent installations at Pearl Harbor with at least a portion of his air striking power.
Naturally had the Japanese submarines around Oahu been able to give him any clue as to the direction in which our fleet had departed from Pearl Harbor before X-day, his movement would have been to the westward; but, failing such information, he might well have decided to deliver an attack on Oahu itself, if only to knock out our shore- based air and thus give greater security to his movements while in Hawaiian waters. His fuel situation would have been causing him considerable anxiety in his planning for future operations. In fact, had no contact been made with his forces on December 6th by our patrol planes, he might well have decided to deliver a late afternoon attack on the permanent installations of Pearl Harbor on December 7th. Assuming such a strike had been delivered from about the same location as the actual attack, he could have expected to recover his aircraft about sunset and steamed during the ensuing night on the western semicircle of 300 miles from Pearl. Presumably he would have been more than willing to have a night action between at least his cruisers and destroyers and our fleet, while avoiding action with his carriers and possibly his battleships. The afternoon attack on Pearl Harbor could have hardly failed to locate his force to the northward of Pearl, and our forces might have headed to the northward on the assumption that it was a hit and run raid. Under these conditions a night action might have taken place during darkness of December 7-8, or the two forces might have missed contact entirely. On the whole, the possibilities in this general situation (with our battleships at sea) might have been as follows: (1) an afternoon air attack on Pearl Harbor December 7th with a night action following; (2) the same attack on Pearl with no contact thereafter; (3) or a daylight engagement on December 7th or 8th to the northward and westward of Oahu. The probable results of any of these might well have altered the actual course of the Pacific war to our detriment.
Certainly, in view of his orders, Admiral Nagumo would hardly have attacked an empty Pearl Harbor unless he was convinced he had not been detected, and consequently it is quite possible the first indication of such an attack to our forces would have been either by radar or patrol plane sighting. In view of the communication facilities available at this time, a sighting of the Jap surface force or radar contact one hour before the attack would have permitted only about one half hour for preparatory action. With such short warning, while considerably more air opposition to the attack would have been presented, the anti-aircraft fire (with the battleships at sea) would have been considerably less; and while the over-all Japanese air losses may have been somewhat greater, this would have been counterbalanced by the damage done to the fuel storage, dry docks, and other permanent installations. Had a night action taken place, our losses would have undoubtedly been greater than those of the enemy, as the Japanese were at this time considerably better prepared for night combat than our fleet. As for a day action, we had only two carriers to oppose six.
All in all, the best we could have hoped for under the conditions of this December 4th IF would have been for a patrol plane sighting of Nagumo’s force on December 6th and a subsequent failure of the two fleets to make contact which, while a possibility, would have been a remote one. At worst, in a day engagement, we might have lost the major portion of our fleet, including two of the three carriers then in the Pacific. Had our two carrier task forces been permitted to operate without the handicap of having their movements restricted by the old battleships, they might have accomplished something.
The third “IF” to be discussed here will treat with the possible alteration of events had a long-range patrol plane search to 700 miles been operating during the first week in December. The actual Japanese track, patrol plane cruising speeds, and the time of sunrise combine to indicate that, had the sector north to northwest from Oahu been covered on December 6th, two planes might have sighted Nagumo’s force between 1330 and 1430 on December 6th. Assuming a median 1330 for the contact, development of the contact, formulation, coding and transmission of the dispatch, etc. the information would probably have reached Pacific Fleet headquarters at Pearl Harbor about 1415. Sunset at this season came earlier than any other time in the year, so that even with the greatest possible celerity of decision and action, the harbor could not have been cleared and a formation effected that evening without acceptance of a grave potential risk from Japanese submarines. In fact, a partial sortie of those large ships in the highest degree of readiness and all available destroyers might have been the logical solution. The Japanese submarines in Hawaiian waters would have undoubtedly reported whatever sortie was effected, and Admiral Nagumo’s air plan would have been modified in consequence. Japanese interrogations after the war have given the information that the Pearl Harbor attack planes had sufficient fuel to attack the fleet as far as 150 miles south of Pearl Harbor, so that unless the battleships at sea had been ordered to “run away from the fight” they might have still afforded a target for the Japanese air attack.
Actually with Admiral Halsey and the Enterprise about 300 miles to the west, a rendezvous with him would probably have been the order. Assuming that all except one or two large ships had sortied on the sixth, the reconnaissance float type Zeros from Nagumo’s heavy cruisers would have reported that the birds had flown, and the Japanese air strike might have been held dear of Oahu pending further information. Our morning patrol plane search from Oahu would have located the Japanese force hut, in view of the vulnerability of the Catalinas and the number of Zeros in the air, such contacts might well have been manifested by the absence of any reports from our planes in those sectors rather than by any positive information.
Of course, had Oahu-based fighters intercepted and shot down the four Zero float planes, the originally planned attack on Pearl Harbor might have been carried out. While it would have met with considerably more air opposition from Oahu fighters, the Zeros which actually expended their effort in strafing targets on the ground would have been diverted to air combat. In addition, the anti-aircraft fire from Pearl Harbor, the far greater portion of which actually came from surface vessels, would have been so materially reduced in volume as to more than compensate for any hypothetical increase in accuracy due to the absence of surprise.
Hence the Japanese bombers and torpedo planes might well have been able to deliver an attack nearly as efficient in both volume and accuracy as that recorded by history. With a paucity of ship targets, the oil tank storage and other permanent installations would have formed most inviting targets of opportunity. On the return of this air strike Admiral Nagumo undoubtedly would have attempted to bring on an engagement. Our commander undoubtedly would have realized by this time how badly he was outmatched in air strength and most probably would have delayed seeking action until reinforced by Admiral Newton with the Lexington. The end result might well have been an engagement d la Midway somewhere between that island and Oahu, but this time with no shore objective to divert Japanese air strength. Assuming even as high as the equivalent of one carrier air group as the combat and operational losses suffered by the Japs in the Pearl Harbor strike, Admiral Nagumo would have still outmatched our air strength in the ratio of 5 to 2 and our losses might have been expected to be as high as six times those of the Japs, or even higher in case the attack on Pearl had been cancelled.
Our final “IF” deals with the possible effect of an eleventh hour warning, either through the medium of timely transmission of late “magic” from Washington, a more efficient and rapid interpretation of radar indications, or a more timely transmission and evaluation of the early morning submarine contacts off the entrance to Pearl Harbor. These items so captured the public imagination when these “failures” were first published that an inordinate amount of inquiry and explanation have been devoted to these minutiae. Broadly speaking, none of these data could have been placed in the hands of the men with authority to evaluate and translate decision into action more than one hour before the first bomb actually dropped. Practically speaking, this would have permitted only a few more fighting planes to have taken the air, more antiaircraft guns to have been manned, and a few water-tight doors to have been closed. A few more Jap planes might have been shot down, but not enough more to have affected materially the damage inflicted by the enemy. In addition, many individuals and groups that day took correct action under the compulsion of indoctrination without specific orders. Who can say whether the omission of many ordinarily required musters, tests, reports, etc., materially hindered or possibly even aided defense efforts in the pitifully few minutes that would have been available?
In summation of the possible alteration in the effects of Pearl Harbor had our four “ifs” governed, we have:
(A) IF it had been decided clearly and definitely on November 27 that Pearl Harbor would probably be attacked in the near future, we might have had:
(1) A remote possibility that the scheduled attack on Pearl Harbor might have been cancelled;
(2) A more probable naval engagement north of the Hawaiian chain with probable losses to our forces of four times those of the Japanese, and including all our carriers then in the Pacific.
(B) IF it had been decided clearly and definitely on December 3rd that Pearl Harbor would probably be attacked in the very near future, we might have had:
(3) A possible attack on an empty Pearl Harbor with the fuel storage and permanent installations as targets;
(4) Either in place of, or in addition to (3), above, a naval engagement to the west of Oahu with our probable losses six to nine times those of the Japanese, and including two of the three carriers then in the Pacific.
(C) IF long range air reconnaissance had been conducted during the first week in December, we might have had a contact with the Japanese attack force on the afternoon of December 6th followed by:
(5) A possible attack on a nearly empty Pearl Harbor with one or two heavy ships, the fuel storage, and permanent installations as targets;
(6) A naval engagement, possibly between French Frigate Shoals and Midway, with our losses six times those of the Japanese, and including two carriers.
(D) IF a late warning by any means had afforded Admiral Kimmel and General Short about one hour for action, we might have had:
(7) A slightly smaller amount of damage to our forces and a somewhat larger loss of Japanese aircraft.
Five of these seven hypothetical results probably would have been more disastrous than the real Pearl Harbor; the seventh would have had no really material effect on history. It is here impracticable to comment adequately on the remaining possibility—the remote chance that the attack might have been cancelled by the Japanese had our entire fleet sortied on December 3rd. Possibly Professor Morison’s comment provides a sufficiently broad basis for further consideration when he says, “On the strategic level, it (the attack on Pearl Harbor) was idiotic. On the high political level it was disastrous.”2
If we grant the force of this quotation, then we have an explanation of why, before December 7th, almost no one believed that Pearl Harbor would be attacked. It was possible, yes, to forecast how such an attack could best be delivered, as witness the Bellinger-Martin estimate. But even that prophetic document does not comment on the possibilities of such an attack being undertaken, and if begins with assumption that if risk of such an attempt is determined to exist, then such and so should be done. Of all the many members of the armed services and civilians with whom the present writer conversed during 1941 prior to December 7th, only one man (then a senior commander in the Navy) expressed a definite conviction that the Japanese would attack at Pearl Harbor and without warning.
Why was the conviction that an attack on Pearl Harbor, while possible, was rather unlikely, so nearly universal among Americans? Was it because we felt instinctively that it would be bad strategy and worse high politics? Or was it just because we thought so differently from the Japanese? Semanticists are beginning to claim the type of actions of a man, or a nation, can be predicted fairly accurately under given conditions if we can properly evaluate the stage of civilization to which he belongs. They claim a peasant will act and feel as a primitive, while a feudal nation will react as did the medieval man. Note that Japan is less than a century away from full-blown feudalism. Further note the statement of Captain Y. Watanabe, gunnery officer on Admiral Yamamoto’s staff, when asked the objective of the attack on Pearl Harbor. “In Japanese tactics we are told when we have two enemies, one in front and one in back, first we must cut in front by sword. Only cut and not kill, but make it hard. Then we attack the back enemy and kill him. This time we took that tactic, having no aim to capture Pearl Harbor but just to cripple it. We might have returned to capture later.” Possibly a semantic approach to the psychological study of a potential enemy can so reinforce conventional intelligence methods as to reduce the risk, when and if World War III occurs, of hostilities opening with a Pearl Harbor II.
A graduate of the Naval Academy in 1919, Admiral Ramsey is a specialist on the subject of air power, his early experience including, among other things, duty as navigator of our first carrier, the Langley, and as commander of torpedo plane squadrons on the U.S.S. Yorktown in 1937. He is the author of many previous articles in the Proceedings on naval aviation and sea power.
1 As published in the United States News of September, 1945.
2 The Rising Sun in the Pacific, page 132, Volume III of History of United States Naval Operations in World War II by Samuel Eliot Morison.