Foreign Relations of the United States: Diplomatic Papers, The Conference of Berlin (The Potsdam Conference), 1945, Volume II

J. C. S. Files

Joint Chiefs of Staff Minutes²

Potsdam, July 24, 1945, 2:30 p.m.

top secret

General of the Army Antonov asked Fleet Admiral Leahy to preside at this, the first tripartite meeting of the Chiefs of Staff at Terminal.³

Admiral Leahy said that he was glad to accept the duties of presiding officer at this session.

Admiral Leahy then asked that General Antonov outline the intentions and plans of the U. S. S. R. with reference to the Japanese.

General Antonov said that Soviet troops were now being concentrated in the Far East and would be ready to commence operations in the last half of August. The actual date, however, would depend upon the result of conferences with Chinese representatives which had not yet been completed.^3a The objective of the U. S. S. R. in the Far East was the destruction of the Japanese troops in Manchuria and the occupation of the Liaotung Peninsula. After the defeat of Japan in combination with the Allied armies it was the Russian intention to withdraw their troops from Manchuria.

General Antonov said that at the present time the Japanese have in Manchuria approximately 20 infantry divisions, two tank divisions, and a sufficient number of depot divisions, separate brigades and separate battalions to bring the total Japanese forces up to a strength of approximately 30 divisions. In addition to these there were approximately 20 divisions of Manchurian troops, making an aggregate of approximately 50 divisions in all on the Russian front.

If the Russian operations were to be successful it was important to prevent the Japanese from strengthening their Manchurian front by reinforcements from China and the Japanese Islands. It was estimated that the Japanese might bring for this purpose 10 divisions from China and 7 from the Japanese Islands. If, therefore, the U. S. S. R. was to be able to carry out its operations successfully it was necessary to prevent any such reinforcement.

General Antonov said he wished to call attention to the fact that there was only a single railroad line connecting Central Russia with the Far East; the effect of this was to limit rail movements of all kinds and effectively prevent any rapid movement of troops.

Admiral Leahy then asked General Marshall to outline the situation of the Japanese with respect to ground troops.⁴

General Marshall said that it is estimated that the Japanese have at present approximately 1,800,000 Japanese troops in Japan proper; there are approximately 500,000 troops in Kyushu and a fairly large garrison in the Ryukyus outside of Okinawa. The Japanese garrison in Formosa has recently been increased to about 260,000 men.

In the Philippines there are now about 12,000 to 14,000 Japanese survivors collected in the mountains of northern Luzon for the final death struggle. In Mindanao there are about 20,000 troops scattered throughout the central plateau, all of the coastline positions having now been lost. In the remainder of the Philippines there are approximately 25,000 troops who are widely scattered.

There are, throughout the Pacific islands, isolated garrisons who are under constant surveillance and periodic bombing and whose presence cause no inconvenience to United States forces. There are a considerable number of isolated Japanese troops in Borneo, in New Guinea and the Celebes, in Bougainville in the Solomons group and in the Bismarck Archipelago. The Japanese troops in the Solomons and the Bismarck Archipelago are confronted by the Australians, who are also taking care of a considerable force in the north central part of New Guinea. All of these island garrisons are suffering from gradual exhaustion of their military supplies. In New Guinea they are suffering, in addition, from malaria and other tropical diseases. The remaining garrisons in Java and Sumatra have been reduced by movements to the Malay Peninsula.

The United States Chiefs of Staff estimate that there are about a million Japanese in China. At the present time the most noticeable movements of Japanese troops have been towards Kyushu. In the last three months two divisions from Manchuria had been identified there and it is understood that these divisions have left in Manchuria the cadres for two additional divisions. Two divisions have recently been moved from Korea to the Japanese homeland. One of these is composed of depot troops and the composition of the other is unknown. In the recent past deceptive measures instituted by U. S. forces have resulted in the concentration of Japanese troops in the Kuriles north of Hokkaido. It is known now, however, that the Japanese are moving troops out of the Kuriles and a division of these troops has recently been identified in Kyushu.

U. S. troops now have firm control of Okinawa where they are busy improving harbors and developing numerous airfields. It is expected

that in addition to the naval and Marine Corps planes now on Okinawa that General MacArthur’s air force will have 2,000 planes there before the end of the summer. On Luzon strenuous efforts are being made to develop the necessary base facilities for incoming troops. Because of harbor destruction and the sinking of 500 ships in Manila Bay this has been a difficult task but satisfactory progress is being made.

With reference to General Antonov’s remark regarding the severing of Japanese communications with Manchuria, General Marshall said it is the present understanding the Japanese communications have been seriously interfered with by U. S. submarine action in the Sea of Japan, and by the continued laying of submarine mines by B–29’s at the western entrance of the Inland Sea near Shimonoseki and the blockade of such harbors on the west coast of Honshu as Niigata.

The ferry service between Japan and Fusan [Pusan] and shipping in the Yellow Sea has been terminated. Ferry service to Fusan has been moved to the ports further north in Korea. Mine laying by B–29’s has extended north along the Korean coast from Fusan to Genzan [Wonsan]. Mines have also been laid in the Inland Sea in the Bungo Channel and in the Bay of Tokyo. Naval air action has extended to northern Honshu and Hokkaido and numerous coastal ports have been attacked by naval aircraft and by direct bombardment. In recent months aircraft based in the Philippines have reduced the normal traffic from ports as far south as Indo-China to Japan from forty convoys a day to none whatever at the present time. By these various actions the Japanese have been compelled to stop all operations at sea except minor operations in the Sea of Japan and coastal lugger traffic in the Java Sea and along the coasts of Malaysia. As a result of increased naval action and mining by super-bombers, there is little likelihood of any Japanese troop movements between Japan and Manchuria. By September or October we expect it to be impossible for the Japanese to move any cargo over this route. It is believed that Japanese operational shipping of one thousand tons and over has been reduced from seven or eight million tons at the beginning of the war to 1¼ million tons at the present time.

In referring to General Antonov’s remarks relating to the movement of Japanese reinforcements from China to Manchuria, General Marshall said that the general movement of Japanese troops in China indicates a withdrawal from the south. Garrisons in Indo-China and to the southward have been cut off by Chinese forces. It appears that the Japanese are establishing a fortress garrison of about 150,000 men for the defense of Hong Kong and Canton. A similar garrison is being established in Shanghai, including Chusan Island. An inland fortress garrison is being established in Hankow. Our evidence indicates that in spite of their efforts to withdraw their forces to the northward, the continued air attacks on the single-track railroad and sabotage by Chinese guerrillas will prevent the Japanese from moving more than a trickle of troops to the north. Not only is the rail route interrupted, but the rolling stock is in bad condition. They are, therefore, dependent largely on water transportation. In the course of time the Japanese could move troops from North China to Manchuria through the Peking–Kalgan and the Tientsin regions.

The redeployment of troops from the European Theater to the Pacific is now well underway. The first troops have reached Manila. Our first requirement is for engineering and similar troops to restore the harbors and prepare cantonments. Six divisions from Germany with the attached corps and army troops are now in the United States. They will be moved from the west coast of the United States as rapidly as shipping is available.

In the Pacific at the present time the principal difficulty is to find ground room for troops and aircraft we wish to deploy there. The early requirement for engineering troops in the Philippines is thus apparent.

The divisions already in the Pacific have largely been withdrawn from combat and are now being reconditioned and trained for the next operation.

The next most important difficulty in the Pacific is the provision of shipping. By the improvement of harbors, by decreasing the turnaround of our vessels and by making all possible air transport available we hope to overcome the shipping shortage.

In closing, General Marshall said that attacks upon Japan from the air and the sea are now proceeding in tremendous volume, but the intensity of these attacks would increase each week.

Admiral King said that he would briefly supplement General Marshall’s remarks. He said that since Yalta the United States Navy had participated in the complete conquest of the Philippine Islands. Commencing in April the conquest of Okinawa and adjacent islands had been accomplished, and bases for land, sea, and air forces were being developed preparatory to the next move against the Japanese homeland. In addition to the Okinawa operation, carrier task forces had attacked air and naval bases in Japan proper. Recently the Third Fleet, under Admiral Halsey, had bombarded the Tokyo area and northern Honshu and Hokkaido. Commencing with the Ryukyus campaign a part of the British Fleet had operated as a task force of the U. S. naval forces. The Japanese navy is now only one-third of its maximum strength and most of the remaining units are of questionable military value, except perhaps for suicide purposes. Naval reconnaissance aircraft now range to the Shantung Peninsula, Korea and the Sea of Japan. Our submarines are operating against the sea communications between Japan and Korea, in Japanese home waters and in the Sea of Japan. We have developed naval bases in Guam and Saipan, in the Marianas group, and are now developing a base in Okinawa.⁵

General Arnold said that he would furnish some additional details regarding the matters discussed by General Marshall. The limited land areas in the Pacific Theater make it impossible to utilize at present all of the large number of airplanes which had been used in the European Theater. When commencing the air campaign against Japan proper we were limited in operations by the airfields we could develop in the Marianas. From these islands the B–29’s performance enabled us to carry out attacks against the Japanese industrial areas in Honshu. During the first part of the campaign Japanese air opposition, as well as anti-aircraft fire, was intense. Navigation problems were most difficult. The weather through which we had to fly had an effect on the ability of the plane crews to carry the maximum weight in bombs. With the increase in the strength of our attacks the opposition by the enemy decreased. After the capture of Iwo Jima we were able to base fighter planes there which were able to accompany the B–29’s on their attacks on Japanese Islands. Not long after the employment of long-range accompanying fighters was initiated the Japanese Air Force assumed a condition of impotency and we have records of many instances when B–29’s reached their objectives without encountering any enemy air opposition. We have learned more about Japanese weather and this and experience gained enabled us to add 30 percent to the bomb load of our B–29’s. With fields established on Okinawa B–24’s will be able to operate to the north of Port Arthur and B–29’s to a range of 200 miles north of Harbin. We will be able to carry maximum bomb loads against Japanese industries and lines of communication in Manchuria. The B–29’s operating from Okinawa will carry a bomb load of 20,000 pounds. The difficulty of operating air units from Okinawa will be appreciated when it is realized that the island is only 80 miles long and that only 48 miles of its length can be used for airfields. This usable part of the island is only six or seven miles wide at the widest part. We expect to operate between 2,000 and 3,500 planes from the fields we are building there.

General Arnold said that the exact proportion of Japanese industry now operating in Manchuria was not known but it was estimated to be about twenty percent.

He said that the Japanese Air Forces now have some 5,000 planes, a larger number than they have ever had before, but their air force is at its weakest point operationally.

The 5,000 planes referred to above include all types of planes—operational and non-operational—reconnaissance, photographic and combat. Of these the Japanese have set aside about 1,200 for suicide operations. These are now concentrated largely in northern Honshu where the crews are being given special training in suicide technique against airplanes both on the ground and in the air and against ships—warships as well as cargo ships unloading at our ports such as Okinawa.

The Japanese have lost many of their best air leaders—most of their experienced pilots and large numbers of their maintenance crews. They are also very short of gasoline and oil. As a result, Army and Navy planes operating over Hokkaido, Honshu, and the Ryukyus rarely encounter more than 70 or 80 planes.

General Antonov asked General Marshall if he thought it would be possible for the Japanese to move large forces from Japan to Manchuria and from China to Manchuria.

In reply, General Marshall said that he believed no troops could be moved from Japan to Manchuria. He thought the Japanese would be unable to move a large number of troops from China to Manchuria by rail but, given time, they could increase their forces in Manchuria from Central China via the Peking–Kalgan route or via Tientsin. The rail line south of Shantung is susceptible to air attack and sabotage. For this reason it would be a slow process to move large numbers of troops over this route.

General Wedemeyer, the United States Commander in China, has 1,000 planes of the Tenth and Fourteenth Air Forces under his command to operate against this railroad.

Continuing, General Marshall said that at the present time 100,000 tons of supplies a month are being moved into China by air over the mountains and via the old Burma Road. Over this route heavy movements of Chinese troops have been made from Burma to China. The movement of troops and supplies to China has been undertaken in order to have ready by August, 15 Chinese divisions of 10,000 men each equipped with American arms, trained by American officers and enlisted men, and directed under American guidance. He said he mentioned this movement of troops and their equipment from Burma since these movements had prevented an increase in the gasoline supply to China. As the equipping of these divisions is completed and the operations to be undertaken succeed, a greatly increased gasoline supply will be available which will enable heavy attacks to be made on the railroad to North China.

Chinese troops in August will attack Fort Bayard, a port on the China Sea north of Hainan and south of Canton. This port is within 150 miles of the area from which the American-trained Chinese troops will advance on Canton and Hong Kong. It had been estimated that one Liberty ship in Fort Bayard was the equivalent of three or four in Calcutta; one transport plane in Fort Bayard was the equivalent of ten or more in Burma, and 20,000 men in Fort Bayard was the equivalent of 150,000 in Burma. All of these advantages would be reflected in the air operations against the railroad in China.

General Marshall said that the Chinese troops had given a good account of themselves in Burma and their effectiveness was encouraging beyond expectations. He thought that with heavy air support the Chinese troops would operate with considerable success against a Japanese withdrawal to the northward.

With support of the Chinese forces by ship rather than through Burma he thought that the air forces would be able to completely destroy the Chinese railroad, and although the railroad could be attacked from Okinawa it would not be a profitable target for aircraft based there.

General Antonov asked if the United States would operate against the Kuriles in order to open the line of communications to Siberia. He said that they had some strength in Kamchatka and would like to assist with some forces, and that he considered opening this sea route to be most important. He also asked if it would be possible for the United States forces to operate against the shores of Korea in coordination with the Russian forces which would be making an offensive against the peninsula.

Admiral King said that it would not be possible to operate against the Kuriles and that he saw no reason why a line of communications could not be maintained through the Kuriles as the passages were wide and deep. In reply to the question in regard to operations against Korea, General Marshall said that such amphibious operations had not been contemplated, and particularly not in the near future. To undertake amphibious operations against Korea would seriously expose our shipping to Japanese suicide attack by air and surface vessels until we had completely destroyed enemy air strength in southern Korea and until certain portions of the Japanese homeland had been brought completely under our control. To stage such an operation would require a great number of assault ships which would be engaged in three landings on Kyushu. There were no additional assault ships which would permit a landing in Korea. With only a small amphibious force landings could be made on the China coast south of Shanghai which would be of great assistance to General Wedemeyer. He realized the importance of Korea to the Russian operations but said that the possibility of an attack on Korea would have to be determined after the landings on Kyushu. He thought that Korea could be controlled from airfields that would be established in Kyushu.

Admiral King said that he hoped and expected that after the Kyushu operation we would have such control over the waters of Japan and Korea that we could establish a line of sea communications through those waters to Vladivostok and the Maritime Provinces.

General Marshall pointed out that we had already severed the line of communications between Korea and the main islands of Japan.

General Marshall said that he had with him some questions which he would leave with General Antonov to be answered at his convenience since he did not think that he would be prepared to give the answers at the present time.⁶

Admiral King said that he would like to call the attention of the Russian Chiefs of Staff to the conversation that took place at Yalta regarding La Perousse Strait, the control of which, we understood, would be undertaken by the Russians by capturing the southern end of Sakhalin Island at as early a time as the Russian Chiefs of Staff thought practicable.⁷

General Antonov said that the first task facing the Russians would be the destruction of the Japanese troops in Manchuria. Because of the distance of Sakhalin, additional troop movements would be required in order to complete its capture in time to be of value in opening La Perousse Strait. Therefore, the attack on southern Sakhalin would be undertaken as a second offensive.

General Marshall then gave General Antonov a book explaining the experiences of our forces in fighting the Japanese which he thought might be of value to him.⁸ He also gave him an estimate of the situation in the Far East.⁸

General Antonov said that he was grateful for the very valuable information which General Marshall had given him and said that it would be truly exploited.

In regard to operations in Southeast Asia under Admiral Mountbatten, Sir Alan Brooke said that the reconquest of Burma had recently been completed but that some Japanese still remained in Burma where they had been cut off by the advance on Rangoon. These Japanese had been making an attempt to join other enemy forces in Siam and five hundred of them had been killed in the last two days. Operations in Burma were being interfered with by the monsoon which was still continuing. When the weather clears, Sir Alan Brooke said that Admiral Mountbatten would continue on towards Siam. In Burma there were the remnants of nine enemy divisions facing the British and behind these remnants was one division in Siam and four in Indo-China.

Sir Alan Brooke said that they were preparing for an operation to secure Malaya and Singapore and to open the Straits of Malacca. The opening of these straits would shorten the line of communications for the support of British forces operating in the Pacific Theater against the main islands of Japan.

In Malaya there were little more than two divisions of Japanese troops which were being reinforced from Java and Sumatra.

Plans were being prepared for a small expeditionary force to cooperate with the United States forces in the attack on Japan. The limiting factor for operations in this area was shipping.

Admiral Cunningham said that only remnants of the Japanese Fleet in the Southeast Asia area remained and that within the last two months the two efficient Japanese cruisers had been sunk. Only two damaged ones remained in Singapore. The British East Indies Fleet was unrestricted in its movements except in the very narrow parts of Malacca Strait.

Sir Charles Portal said that the British and United States air forces in Southeast Asia maintained complete supremacy over the Japanese air forces in that area. His estimate of the strength of enemy air forces in Burma, Siam, Malaya, Sumatra, and Indo-China on 15 July was 260 operating aircraft plus 150 training units. He said he considered any substantial increase in air strength most unlikely and that Admiral Mountbatten had ample aircraft for his future operations.

Admiral Leahy asked General Antonov if he desired to ask the British Chiefs of Staff any questions, to which General Antonov replied that he did not.

General Antonov said, however, that he would require some time to consider the questions which had been presented to him by General Marshall and that when he was prepared he would like to arrange another meeting. He said he was very grateful for the information that had been furnished him by the United States and the British Chiefs of Staff.

Admiral Leahy expressed the appreciation of both the United States and the British Chiefs of Staff for the information given to them by the Russian Chiefs of Staff.

2. The papers of the Joint Chiefs of Staff indicate that “These Minutes were transcribed from notes taken by the United States Secretaries, Combined Chiefs of Staff.”
3. This was the only tripartite meeting of Chiefs of Staff at the Conference.
4. Cf. ante, p. 45, and document No. 1418, post.
4. Cf. the two maps facing this page: (1) “The Armed Forces: Ground, 18 June 1945” (annex to appendix B to C. C. S. 643/3) and (2) “Ground Situation in China, 6 June 1945” (appendix D to C. C. S. 893/1).
5. Cf. the map facing p. 350: “Pacific Situation, 1 July 1945” (appendix A to C. C. S. 893).
6. For the text of the questions referred to, see document No. 1279, post. For the answers, see post, pp. 409–413.
7. See Foreign Relations, The Conferences at Malta and Yalta, 1945, pp. 835, 840.
8. Not printed.
8. Not printed.