What We Knew

From "The Real Infamy of Pearl Harbor"

Percy L. Greaves, Jr.

Before presenting the testimony relating to December 7th, it would be helpful to review the information available to Generals Marshall, Gerow and Miles as well as Secretary of War Stimson before they left their respective offices on December 6th. There was a mounting accumulation of facts and events that could not help but create an increasingly apprehensive atmosphere which called for an ever higher degree of alertness for possible Japanese action. There were a myriad of such developments, but only the highlights will be mentioned.

On November 5, 1941, Marshall and Stark signed a joint memorandum for Roosevelt in which they concluded that

The basic military policies and strategy agreed to in the United States-British Staff conversations remain sound.... Military action against Japan should be undertaken only in one or more of

several contingencies. These included a Japanese movement

against the territory or mandated territory of the United States, the British Commonwealth, or the Netherlands East Indies.

It also included the movement of Japanese forces across a specified line previously described. Because of their desire for more time to build up forces in the Far East, their final recommendation was:

That no ultimatum be delivered to Japan.

That same day a MAGIC message told them that:

Because of various circumstances, it is absolutely necessary that arrangements for the signing of this agreement be completed by the 25th of this month

if Japanese-U.S. relations are to be saved

from falling into a chaotic condition.

A week later they read in MAGIC that:

the date set forth ... is absolutely immovable under present conditions. It is a definite dead-line and therefore it is essential that a settlement be reached by about that time.... The situation is nearing a climax ... time is indeed becoming short.

This was further confirmed three days later when a November 15th Tokyo message closed:

The date set forth ... is an absolutely immovable one. Please, therefore, make the United States see the light, so as to make possible the signing of the agreement by that date.

A November 16 message was read on November 17, stating:

The fate of our Empire hangs by the slender thread of a few days, so please fight harder than you ever did before.... I set the deadline ... and there will be no change. Please try to understand that. You see how short the time is; therefore, do not allow the United States to sidetrack us and delay the negotiations any further. Press them for a solution on the basis of our proposals, and do your best to bring about an immediate solution.

Final Deadline Set

On November 19, a MAGIC message informed them that if the U.S.-Japan diplomatic negotiations failed:

It is most probable that diplomatic relations between the two countries would be broken off immediately.

The Japanese Ambassadors in Washington sought instructions from Tokyo as to reducing Japanese personnel in the United States.

On November 22nd, the Ambassadors' plea to Tokyo for more time was answered:

It is awfully hard for us to consider changing the date we set.... There are reasons beyond your ability to guess why we wanted to settle Japanese-American relations by the 25th, but if within the next three or four days you can finish your conversations with the Americans; if the signing can be completed by the 29th, (let me write it out for you-twenty-ninth); if the pertinent notes can be exchanged; if we can get an understanding with Great Britain and the Netherlands; and in short if everything can be finished, we have decided to wait until that date. This time we mean it, that the deadline absolutely cannot be changed. After that things are automatically going to happen.

Two days later, on the 24th, our top Washington officials read a Japanese intercept stating that:

The time limit set ... is in Tokyo time.

This is a day (14 hours) earlier than Washington time. On Tuesday, November 25, the War Cabinet, including Marshall and Stimson, met at the White House. Stimson's diary notes the President:

brought up entirely the relations with the Japanese. He brought up the event that we were likely to be attacked perhaps (as soon as) next Monday [December 1], for the Japanese are notorious for making an attack without warning, and the question was what we should do. The question was how we should maneuver them into the position of firing the first shot without allowing too much danger to ourselves. It was a difficult proposition.... The others brought out the fact that any such expedition to the South as the Japanese were likely to take would be an encirclement of our interests in the Philippines and cutting into our vital supplies of rubber from Malaysia. I pointed out to the President that he had already taken the first steps toward an ultimatum in notifying Japan way back last summer that if she crossed the border into Thailand she was violating our safety and that therefore he had only to point out (to Japan) that to follow any such expedition was a violation of a warning we had already given.

Our military and naval advisors had warned us that we could not safely allow the Japanese to move against British Malaysia or the Dutch East Indies without attempting to prevent it.

A number of Japan's intercepts were translated and circulated on November 26th. Perhaps the most informative was one sent on November 14, from Tokyo to Hong Kong and eleven other Chinese cities. It read in part:

Though the Imperial Government hopes for great things from the Japan-American negotiations, they do not permit optimism for the future. Should the negotiations collapse, the international situation in which the Empire will find herself will be one of tremendous crisis. Accompanying this, the Empire's foreign policy as it has been decided by the cabinet ... is:

a. We will completely destroy British and American power in China.

b. We will take over all enemy concessions and enemy important rights and interests (customs and minerals, etc.) in China....

We will cope with a world war on a long-time scale. Should our reserves for total war and our future military strength wane, we have decided to reinforce them from the whole Far Eastern area. This has become the whole fundamental policy of the Empire....

Please keep absolutely quiet the existence of these decisions and the fact that they have been transmitted to you.

On November 26, our officials read another highly interesting intercept sent the day before, probably the 24th U.S. time, from Japanese forces poised at Hanoi to Tokyo:

We are advised by the military that we are to have a reply from the United States on the 25th. If this is true, no doubt the Cabinet will make a decision between peace and war within the next day or two ....

Should ... the negotiations not end in a success, since practically all preparations for the campaign have been completed, our forces shall be able to move within the day....

State Department Surrenders

On November 26th, that same day, Roosevelt summoned Hull to the White House and, without consulting his military and naval advisors, authorized Hull to hand the Japanese Ambassadors an ultimatum to Japan that it was known Japan could not accept.

On November 27, Hull told Stimson:

I have washed my hands of it and it is now in the hands of you and Knox-the Army and the Navy.

Stimson then checked with Roosevelt, consulted with Knox, Stark and Hull, before preparing with Gerow a message "we shall send to MacArthur" over Marshall's signature. A similar message was incidentally sent to Hawaii.

It was also the date of a joint Marshall-Stark memorandum to FDR, the Commander in Chief that stated:

If the current negotiations end without agreement, Japan may attack: the Burma Road; Thailand; Malaya; the Netherlands East Indies; the Philippines; the Russian Maritime Provinces.

Marshall and Stark again asked for more time until more men and material reached the Philippines. However, they stood by their agreements with the British and Dutch, while asking that a joint British-American warning be sent to Japan if she should advance into Thailand.

November 28 brought alarming indications that Japan was getting ready for action. A telephone conversation the day before between the Tokyo Foreign Office and one of the Japanese Ambassadors was taped, translated and decoded. It told us that "a crisis does appear imminent." That same day, FDR and his War Cabinet also read a Tokyo cable to Japan's Washington Ambassadors. This cable revealed Japan's highly negative reaction to our ultimatum of the 26th.

Well, you two Ambassadors have exerted superhuman efforts but, in spite of this, the United States has gone ahead and presented this humiliating proposal. This was quite unexpected and extremely regrettable. The Imperial Government can by no means use it as a basis for negotiations. Therefore, with a report of the views of the Imperial Government on this American proposal which I will send you in two or three days, the negotiations will be de facto ruptured. This is inevitable. However, I do not wish you to give the impression that the negotiations are broken off. Merely say to them that you are awaiting instructions.... From now on do the best you can.

The reports from the Philippines about the Japanese expeditionary force moving south were so alarming to Stimson on November 28th that he personally took them to FDR in the White House. 25,000 Japanese troops were going to land somewhere. Later that day, there was a meeting of the War Cabinet at the White House. Stimson's diary reports:

It was now the opinion of everyone that if this expedition was allowed to get around the southern point of Indochina and go off and land in the Gulf of Siam, either at Bangkok or further west, it would be a terrific blow at all of the three Powers, Britain at Singapore, the Netherlands, and ourselves in the Philippines. It was the consensus of everybody that this must not be allowed. Then we discussed how to prevent it. It was agreed that if the Japanese got into the Isthmus of Kra, the British would fight. It was also agreed that if the British fought, we would have to fight....

It further became a consensus ... that the only thing for us to do was to address it a warning that if it reached a certain place, or a certain line, or a certain point, we should have to fight.

War Not a Dream

On Saturday, November 29th, Hull met with the British Ambassador. He informed him that he had told our Army and Navy officials that the diplomatic phase "was virtually over." Then "speaking in great confidence" he said

that Japan may move suddenly and with every possible element of surprise and spread out over considerable areas.

On Monday, December 1st, the recipients of MAGIC read a Tokyo to Berlin message that stated:

The conversations begun between Tokyo and Washington last April ... now stand ruptured-broken.... In the face of this, our Empire faces a grave situation and must act with determination. Will Your Honor, therefore, immediately interview Chancellor HITLER and Foreign Minister RIBBENTROP and confidentially communicate to them a summary of the developments.... Say very secretly to them that there is extreme danger that war may suddenly break out between the Anglo-Saxon nations and Japan through some clash of arms and add that the time of the breaking out of this war may come quicker than anyone dreams....

Say that by our present moves southward we do not mean to relax our pressure against the Soviet and that if Russia joins hands tighter with England and the United States and resists us with hostilities, we are ready to turn upon her with all our might; however, right now, it is to our advantage to stress the south and for the time being we would prefer to refrain from any direct moves in the north.

That same day we read Tokyo's instructions for her embassies in London, Hong Kong, Singapore and Manila to destroy their code machines while Washington was informed on how to destroy theirs by chemical means.

On Tuesday, December 2nd, these matters were all discussed at the White House, including proposed FDR messages to Congress and the Japanese Emperor. Stimson met with Marshall, Miles and Gerow concerning their attempts to speed up supplies to the Philippines. Stimson cancelled an out-of-town engagement "in order to stay in Washington over the week end."

Japan's Moves Known

On Wednesday, December 3rd, our War Cabinet read Tokyo's instructions to her Washington Ambassadors to destroy one of their two "Purple" machines and certain other codes. As a result, G-2's Bratton sent a man to observe the Japanese Embassy and confirm the fact that papers were being burned. As Bratton later testified, this "meant that time was running out and the approach of the crisis."

On Thursday, December 4th, we ordered our representatives in Tokyo, Bangkok, Peiping, Tientsin and Shanghai to destroy our top code system. Guam was told to "destroy all secret and confidential publications and other classified matter" with minor exceptions which they should "Be prepared to destroy instantly in event of emergency." The "Winds Execute" message, about which there has been so much controversy, was received. This indicated Japan's break with the United States and Great Britain, but not Russia.

On Friday, December 5th, our War Cabinet read a December 1 Tokyo order to her London Embassy to dispose of its code machine and to report back when that was done.

Saturday, December 6, produced more evidence that Japan was on the move. On that date we first read a circular MAGIC message of December 2, in which Japan ordered her diplomatic representatives abroad to start "the burning of all their telegraphic codes." That order had been issued to all Japanese officials in North America and the South Seas, as well as those in British and Netherlands territories. Our War Cabinet also read a Japanese December 3rd Rome to Tokyo message reporting on a meeting of Japan's Ambassador with Mussolini in which Mussolini was asked if Japan declared "war on the United States and Great Britain ... would Italy do likewise immediately? Mussolini replied: 'Of course'." That same Saturday morning the members of our War Cabinet read a Japanese December 5th Washington to Tokyo message stating, "We have completed destruction of codes" except for the one "Purple" machine needed for receiving the expected reply to the United States ultimatum of November 26.

Still more alarming were the reports from both Admiral Hart in the Philippines and the British, via London, that large Japanese convoys had been seen moving south. Even more alerting was the report that at least one of these convoys had crossed the line which Marshall and Stark had on November 27 told Roosevelt was "a threat to Burma and Singapore.,, In that case the

"United States, British and Dutch military authorities in the Far East [had] agreed that joint military counter-action against Japan should be undertaken."

The End Approaches

Our War Cabinet members also read Tokyo's orders for the departure from the United States of certain important Japanese nationals. Then, on Saturday afternoon, December 6, the intercepted Pilot message informed those privy to MAGIC that the long awaited Japanese reply to our ultimatum would soon be on its way from Tokyo, to be held for delivery at a specified time. As we had learned on November 22, that specified time would undoubtedly be when "things are automatically going to happen."

The 14 part reply began coming in that Saturday afternoon, December 6th. At the White House, a young Navy Lieutenant was detailed to remain after hours to deliver to Roosevelt material "of such importance that the President expected to receive it." The Lieutenant was told that "during the evening Captain Kramer would bring up some "magic" material and that I was to take it and give it immediately to the President." Meanwhile, the President was busy redrafting a face saving message which went off to the Japanese Emperor at 9 p.m., with an announcement to the press.

At the War Department, the urgency that Saturday afternoon was such that several Army cryptographers were summoned from their homes to expedite the decoding of the anxiously awaited Japanese reply. To keep him informed of important developments, Marshall had Colonels on duty around the clock at his office and orderlies at his residence up to 10 p.m. or, when he was out, until he returned. His office, home and bedside had secure telephones passing through the White House switchboard. Yet, according to Marshall's original testimony before the JCC, he wanted the world to believe that he, like Stark, was unaware of all this quickening of developments crying out for his attention and action.

The first time Stark and Marshall testified, each, in turn, implied that he was following his usual Sunday morning activities and weekend routine. As Marshall stated it, "the probability is" that he was at home on Saturday evening and that he took his habitual horseback ride on Sunday morning. Stark had no memory whatsoever as to where he was that Saturday night. As regards the time of his arrival at his Navy Department office on Sunday, December 7, 1941, Stark's first reply was:

I usually got down to the office on Sunday mornings around 10:30 or 11 o'clock. I was lazy on Sunday mornings unless there was some special reason for getting up early. I usually took a walk around the grounds and greenhouse at the Chief of Naval Operations' quarters and didn't hurry about getting down and my usual time, as I recall, was about 10:30 or 11. What time it was that particular Sunday morning I couldn't go beyond that.

The memory of a member of Stark's December 6 theater party forced Stark to revise his earlier testimony that he did not know his whereabouts that Saturday evening or recall the fact that Roosevelt had asked him to phone late that night. Stark thus learned there was a "special reason for getting up early" that Sunday morning. Testimonies of subordinates placed him in his office as early as 9 a.m. or a few minutes later. Unfortunately, no witness enlightened the JCC as to the actual whereabouts of Marshall during many of these crucial hours.


From The Journal of Historical Review, Winter 1983-84 (Vol. 4, No. 4), pages 467-474.