ESTIMATE OF THE SITUATION

ATTACK ON HAWAIIAN AND ALASKAN BASES

PART I - MISSION

The Problem

1.          There are indications that the enemy will make a strong simultaneous effort, commencing after May 26, 1942, to -

(a)  Capture MIDWAY for possible subsequent operations against OAHU, and

(b)  Capture an advanced position in the ALEUTIAN ISLANDS.
The problem here considered is how to deal with that

enemy effort, while continuing to carry out tasks assigned but not directly related to this problem.

The Situation

2.          The basic task of the Commander-in-Chief, U.S. Pacific Fleet, which applies is:

"covering and holding the line HAWAII-MIDWAY and maintaining its communications with West Coast".

          The Commander-in-Chief, Pacific Ocean Areas, is assigned, among others, the following supplementary tasks:

"(a) Hold island positions between the United States and Southwest Pacific Area necessary for security of the line of communications between these regions and for supporting naval, air, and amphibious operations against Japanese."

"(d) Support defense of the continent of North America."

"(e) Protect essential sea and air communications."

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3.    The following is quoted from a message from COMINCH:

"I consider that our appropriate strategy is to make strong concentration HAWAIIAN AREA and ---- to employ strong attrition tactics and not allow our forces to accept such decisive action as would be likely to incur heavy losses in our carriers and cruisers.

"Create for the defense of ALASKA the North Pacific Force comprising northwest sea frontier forces plus such western sea frontier forces as you elect to include sound school destroyers and submarines plus such Fleet units as you can make available all preferably to be concentrated initially at KODIAK and/or COLD BAY."

4.    The Commander-in-Chief, U.S. Pacific Fleet will employ the major part of his forces to repel these attacks. He will expect full cooperation from Army forces stationed in ALASKA.

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PART II - SURVEY OF OPPOSING STRENGTHS

1. (a) The Japanese have just experienced a setback in the NEW BRITAIN - NEW GUINEA Area. In spite of this, their morale is high.

(b) It is to be expected, that the planning for this campaign will be excellent and the preparations complete. They are indicated having a rehearsal for parts of the campaign.

(c) Their planes, are generally speaking, of greater range than ours. Their fighters out-perform ours.

(d) They have amply demonstrated their ability to use their carrier air with great ability. We can no longer under-estimate their naval air efficiency.

(e) On the other hand, our men are just as brave, and those who have been properly trained are believed to be better than their opposite Jap number. Our Army is untried except in Bataan. The Army air has not demonstrated that it has the ability to coordinate with surface forces, and they are not very successful in hitting mobile targets with their high altitude bombers.

(f) Our submarines have demonstrated considerable superiority. Division tactics have not been tried out against the enemy.

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2.     Character of the Theater.

(a) Hydrography, topography. The Hawaiian Sea Frontier presents no problem. Ships up to the size of CAs can enter and berth at MIDWAY, but must exercise extreme caution.

   In the ALASKAN Sector navigation is difficult because of fog. Charts are only fairly accurate. Harbors are generally poor from the viewpoint of the fair weather sailor. The best anchorage for a Fleet is at COLD HARBOR, but it has no resources. The islands are rugged and very thinly populated and will not support troops.

(b) The Weather. The normal trades are expected in the Hawaiian Islands Area, while in the Aleutians south of the chain overcast weather with fog and occasional rain will be an average condition. North of the Aleutian chain there will be a somewhat higher percentage of good flying weather.

(c) Daylight will be from about 0341 to 2014 in Latitude 25°N on June 1st. In Latitude 50°N It will be from about 0023 to 2342.

    There will be a full moon on June 1st.

(d) The following distances are pertinent:

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2.     (Continued)

3.     Information.

(a) Our sole source of information for this problem is RI and CI. The enemy may be deceiving us.

(b) We may expect the enemy to have had full information prior to December 7, 1941. Since that time he has not had such good opportunities. Nevertheless he spotted the return of Task Force 16 in April due to our radio carelessness.

(c) Communication facilities are considered equal, with the exception of our ECM.

4.     Enemy Forces.

(a) Ultimate Japanese strength which will be employed In each sector cannot be accurately determined at this time.

In the Hawaiian sector he may employ:

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4.     (Continued)

In the Alaskan Sector he may employ:

This force will escort and cover auxiliary types consisting of transports, landing boat carriers, cargo vessels, and tankers.

(b) Shore based air can only be employed by some refueling method such as fueling seaplanes from submarines and/or tankers, and using CVs to act as staging points.

5.     Bases.

The nearest bases are too far distant for consideration. He will be well over 2000 miles from any good base support.

6.     Own Forces.

(a) Battleships.

 We have seven battleships on the Pacific Coast. All of them can be moved westward, but because of entire lack of air support and inadequacy of screening vessels they will be kept where they are at the present. They could hardly be secure at Pearl during the period of this estimate because of the strong probability of an air raid.

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6.     (Continued)

(b) Carrier Task Forces.

(1) Task Force SIX­TEEN should ar­rive in the OAHU area about May 26th. De­part­ing OAHU 28 May it can ar­rive off MID­WAY, fu­eled, about 1 June.

(2) Task Force SEVENTEEN will arrive Pearl about May 28th. The YORKTOWN is damaged and must receive plane replacements. It is possible that she can be placed in service four days after arrival Pearl. If she cannot be given adequate temporary repairs in that time she will be sent to BREMERTON at once.

(3) The SARATOGA will be ready at San Diego June 5th. She could, arrive in the critical area of the Central Pacific only if the Japs are considerably later than now expected.

(4) The WASP will not arrive in time to be considered.

(5) The LONG ISLAND is not suitable as a Carrier Task Force nucleus for present operations but might be used after June 15th.

(c) North Pacific Force.

 This force is being formed at the direction of the Commander-in-Chief, U.S. Fleet. It comprises all of the forces which can reach Alaskan waters during the first week in June.

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6.     (c) (Continued)

As Task Force EIGHT, this will eventually comprise: 2 CA, 3 CL, 12 DD, PG, 1 AVP, 1 AM, 14 YP, 4 AMC, 15 CG, 6 SS, 20 PBY-5A, 9 VSO and all Army aircraft that can be made available.

The major part of this task force can rendezvous at COLD BAY or KODIAK about June 5th.

Being opposed to a force containing carriers, it must depend very heavily on land based air.

(d) Escorts.

 All of the remaining surface forces are assigned to escort duty.

(e) Submarines.

 At daylight May 26th submarines will be disposed off MIDWAY as follows:

 1 - 50 miles NW of MIDWAY.

 1 - 50 miles NNW of MIDWAY.

 3 - in the arc 215-315 from MIDWAY distant 175

     miles.

 Eight more submarines will be ready at Pearl between May 24 - 30 to take up offensive patrol in the MIDWAY - OAHU Area.

 Other submarines of the Pacific Fleet not under overhaul are on patrol in enemy waters.

(f) Oilers.

(1) The COMET with ten days oil for Task Force EIGHT is being sent to KODIAK for orders. The SABINE is available for that force also.

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6.     (f) (Continued)

 (2) Other oilers will be used as necessary in the Hawaiian Sea Frontier.

(g) Aircraft.

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6.     (Continued)

(h) Bases

(1) Pearl Harbor is being cleared of shipping as far as possible.

(2) Midway can be used as a staging point for Army bombers.

(3) Alaskan bases are shown in Annex "A" to Task Force EIGHT Operation Plan No. 28-42.

7.     Logistics.

The enemy will have a difficult logistic problem. Because of this the time spent by their combatant types east of 180° will be strictly limited. Should they establish themselves in Alaska or Hawaii their logistic supply will be an immediate objective of the Pacific Fleet forces.

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7.     (Continued)

Own logistic supply will mainly be from Pearl. Small Navy tankers and supply ships now assigned to Alaska cannot be diverted to supply Task Force EIGHT.

8.     Summary of Strength and Weakness Factors.

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8.     (Continued)

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PART III - ENEMY COURSES OF ACTION

1.     The enemy knows our build­ing pro­gram - and that in time - our forces will be suf­fi­ciently strong to take the of­fen­sive. He fur­ther knows our de­fenses are in­ad­e­quate now - but grad­u­ally being strength­ened. Hence, from the time fac­tor alone, such op­er­a­tion should be con­ducted at the ear­li­est pos­si­ble time. While he is "ex­tended", he is able to as­sem­ble a con­sid­er­able force - as most of the oc­cu­pied ter­ri­tory is un­able to make any real ef­fort. He knows that AUS­TRALIA is being heav­ily re­in­forced from the United States and would un­doubt­edly de­sire to cut that sup­ply line. But he may also con­sider MID­WAY to be just an­other WAKE and ALASKA un­de­fended. Re­gard­less of our ideas of his strate­gic pos­si­bil­i­ties, the pur­pose here is to dis­cuss im­me­di­ate pos­si­bil­i­ties.

2.     To hamstring our efforts to build up facilities for the offensive we conclude that he will:

(a) Attempt to capture MIDWAY.

(b) Raid OAHU.

(c) Attempt to secure an advance position in the

    ALEUTIAN Islands.

3.     It is believed that his forces will depart for the ALEUTIANS from a point in northern Japan on May 25 or 26; and that the Hawaiian forces will depart from the SAIPAN Area a bit later. If these beliefs are accepted our opposing forces should be in initial positions in the ALASKAN Sector by June 1st and in the MIDWAY - OAHU Sector June 3rd.

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PART IV - OWN COURSES OF ACTION

1.     We have decided:

(a) To retain the battleships on the West Coast.

(b) To employ Task Force SIXTEEN to the northeast of MIDWAY initially as soon as possible.

(c) To employ Task Force EIGHT in the ALEUTIANS.

(d) To initially employ a submarine screen of 6 fleet submarines off MIDWAY.

(e) To employ Task Force SEVENTEEN in the MIDWAY - OAHU Area if temporary repairs can be made at Pearl. Otherwise the YORKTOWN will be sent to Bremerton.

(f) To expedite the arrival of the SARATOGA in the HAWAIIAN Area.

(g) To reinforce the submarine screen with 6 fleet submarines at Pearl as soon as possible.

(h) To reinforce MIDWAY with PBYs, AA, and a small Raider Group.

(i) To alert forces in the HAWAIIAN Area.

(j) To clear Pearl Harbor of ships as much as is possible.

(k) To hold Army bombers enroute to AUSTRALIA at OAHU during the present emergency.

(1) To use MIDWAY to stage Army bombers to enemy carriers.

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2.     Danger from submarines and other raiders along the Pacific lines of communications requires the continued use of convoys and escorts.

3.     Not only our directive from Commander-in-Chief, U.S. Fleet, but also common sense dictates that we cannot now afford to slug it out with the probably superior approaching Japanese forces. We must endeavor to reduce his forces by attrition - submarine attacks, air bombing, attack on isolated units. The principle of calculated chance is indicated, as set forth in a letter of instructions to Task Force EIGHT. If attrition is successful the enemy must accept the failure of his venture or risk battle on disadvantageous terms for him.

4.     There is the suggestion that the enemy will attempt to trap our surface forces. Our air umbrella will assist in preventing that.

5.     While the dif­fi­culty of plac­ing our sub­marines within reach of the enemy is ex­tremely great, and de­pen­dent to a large ex­tent on chance, the risk to them is no more than nor­mal and we only do it at the ex­pense of ul­ti­mate re­duc­tion in of­fen­sive pa­trol in close to the enemy home­land. The plac­ing of sub­ma­rine leav­ing Pearl May 28-30 will de­pend some­what on the RI and CI in­for­ma­tion.

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PART V - DISPOSITIONS AND FUTURE DECISIONS

1.     More information of the enemy is expected. On present information the following, not indicated in Part IV, is planned:

(a) All submarines available in the Hawaiian Area will be placed on a scouting line to the westward of Midway. They are assigned patrol sectors until contact. On contact they will close in for attack without regard to the assigned sectors.

(b) The SARATOGA will be the carrier of a new task force which will be assigned to the Striking Forces operating in the critical area.

(c) Key personnel under orders to other stations will be retained in present duties until further orders.

(d) Leave and liberty for officers and men will be cancelled until further orders.

(e) Extreme care will be used to prevent the enemy from gaining information of own deployment by radio or otherwise.

(f) The Amphibious Force at San Diego will be put on 48 hours notice in order that it may load and retake any positions captured by the enemy.

(g) Part of a marine Raider Battalion will be retained at Pearl for use in eventualities.

2.     The disposition of the YORKTOWN should be determined by May 28th.

3.     An Operation Plan for MIDWAY Area will be issued to all concerned prior to the departure of major forces.

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