Executive Secretariat Files

Note by the Executive Secretary ( Souers ) to the National Security Council

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NSC 49

The enclosed report, prepared by the Joint Chiefs of Staff on the subject and forwarded by the Secretary of Defense pursuant to the request contained in Reference A, is circulated herewith for the information of the National Security Council and for the use of the Department of State in undertaking its initial studies of the present adequacy of NSC 13/3.

Sidney W. Souers
[Page 774]

Report by the Joint Chiefs of Staff

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Strategic Evaluation of United States Security Needs in Japan

The Japanese Islands are of high strategic importance to United States security interests in the Far East, primarily because of their geographic location with respect to the trade routes of the North Pacific, the exits and entrances of the Sea of Japan, the East China and Yellow Seas, and, to a lesser degree, the ports of Asia north of the Shanghai–Woosung area, inclusive. Japan, also because of her geographic location, could under USSR control be used as a base for aggressive action directly against United States bases in the Western Pacific, in anticipation of step-by-step advances eastward and to the Southeast Asia region. Conversely, United States control of Japan, either directly or indirectly, will not only deny to the USSR an extremely important strategic base for aggressive or defensive action but also, in the event of war, will make available to us strategic outposts for early denial to the USSR, and eventually for control or neutralization by us, of the Sea of Japan and the Yellow and East China Seas. In addition, it would provide us with staging areas from which to project our military power to the Asiastic mainland and to USSR islands adjacent thereto.
Japan’s strategic importance is increased by her manpower and her industrial potentials. These several potentials could, under readily foreseeable circumstances, and, despite the logistic demand that would need to be met in making her support useful, have great influence either for or against the interests of the United States in the event of global war.
The ability of the Japanese to wage both aggressive and defensive war was proven in the last world conflict. It is almost inconceivable that the Japanese manpower potential would be permitted to continue in peaceful pursuits in the event of another global conflict. Under USSR control, Japan probably would provide both the arsenal personnel and the manpower for aggressive military campaigns in the Pacific and to the southwest. If United States influence predominates, Japan can be expected, with planned initial United States assistance, at least to protect herself and, provided logistic necessities can be made available to her, to contribute importantly to military operations against the Soviets in Asia, thus forcing the USSR to fight on the Asiatic front as well as elsewhere.
From the military point of view, the ultimate minimum United States position in the Far East vis-à-vis the USSR, one to which we [Page 775] are rapidly being forced, requires at least our present degree of control of the Asian offshore island chain. In the event of war, this island chain should constitute in effect a system of strong outposts for our strategic position. It would have only limited offensive value, however, and might well be untenable, if any major portion of the chain, such as Japan, were unavailable at the outset of the struggle.
The ability of the United States to derive full strategic advantage from the potentialities of Japan and to deny Japan’s ultimate exploitation by the USSR will depend largely on the course we follow from now on with respect to Japan. This course should, accordingly, take into account the essential objectives, from the military viewpoint, of denying Japan to the Soviets and of maintaining her orientation toward the Western Powers.
With reference to the specific questions in the Acting Secretary of State’s memorandum to the Executive Secretary of the National Security Council, dated 23 May 1949:*
The position regarding bases set forth in paragraphs 5 and 6 of NSC 13/31 is still satisfactory from the military viewpoint, on the assumption that events permit a peace treaty to be worked out that adequately safeguards the Western orientation of Japan. The Navy Department has examined the possibilities of Okinawa for development as a naval base and has determined that it is not suitable as a year-around naval base because of unfavorable meteorological and hydrographic features. The Joint Chiefs of Staff, therefore, consider that arrangements for the continued use of Yokosuka as a base are of major importance. To provide against future contingencies, the peace treaty should not be such as to preclude bilateral negotiations for base rights in the Japanese main islands;
If it should prove impracticable or impossible to obtain bases on the Japanese main islands, bases on Okinawa or other islands of the Ryukyus along with other U.S. bases in or near the Pacific would not meet our essential needs. If a Japanese peace treaty is effectuated the retention of our Western Pacific base system, exclusive of the Japanese main islands, would still be of the utmost strategic importance, and the strategic need for prevention of unfriendly control of Formosa would be increased.
The Joint Chiefs of Staff are convinced that it would be both impracticable and inadvisable for bases or facilities in Japan, either under a continuation of the occupation or otherwise, to be on a completely self-supporting basis and to be manned by military personnel on a garrison basis unaccompanied by dependents. Such arrangements would tend to defeat the purpose of the occupation, since the stabilizing influence of the occupation forces would be vitiated if they were so concentrated at various remote points as to be largely unseen by the population. Further, a morale problem of major dimensions would [Page 776] result and the efficiency and effectiveness of the occupation forces would be jeopardized.
In view of the fact that NSC 13/3 reserved a final United States position concerning the post treaty arrangements for Japanese military security “until the peace negotiations are upon us”, and since agreement of the Joint Chiefs of Staff with the terms of the position set forth in that paper was with the understanding that it was, generally speaking, an interim position (and one which could not, when drafted, take into account the subsequent debacle in China), it is believed that some general discussion, in addition to the specific comment above, is in order.
From the military viewpoint, it is clear, as discussed initially in this memorandum, that the developing chaos on the Asiatic mainland, together with its communistic trend, makes it vital that, with or without a peace treaty, the orientation of Japan towards the West be assured. At the same time, the difficulty of achieving and maintaining such assurance has increased and it can be foreseen that economic and political pressure may well cause the problem to become very great indeed. This makes the question of Japanese internal security more important than ever. In turn, and commensurate with the degree to which Japanese western orientation is maintained, Japan’s capacity for self-defense must be developed against the time when it may be determined by the Soviets that overt aggression by them or their satellites is their only means for gaining control over Japan.
With these points in mind, the Joint Chiefs of Staff are of the opinion, from the military point of view, that a peace treaty would, at the present time, be premature since the continuing Soviet policy of aggressive communist expansion makes it essential that Japan’s democracy and western orientation first be established beyond all question, and since global developments are still in such a state of flux that measures leading to the risk of loss of control of any area might seriously affect our national security.
If peace negotiations are to be undertaken in the near future, they believe that the following safeguards should be included in order that our own national security interests may not be jeopardized and in order that the Far East communistic expansion plans of the Soviets may be held in check at least as far as Japan is concerned:
There should be prior assurance of Japan’s economic, psychological, and political stability, and of her democracy and western orientation;
Japan’s internal security forces must be adequate not only for maintenance of order but for protection against sabotage of vital installations. This may involve stronger internal security forces than were thought to be essential prior to the current overrunning of China;
Since there can be no guarantee in the present world situation of the sovereignty of a defenseless Japan, there should be plans, as [Page 777] previously recommended by the Joint Chiefs of Staff, for limited Japanese armed forces for self-defense to be effectuated in war emergency, and, in any case, unless the general situation makes it clearly unnecessary, prior to departure of occupation forces from Japan; and
No definite time should be set in the peace treaty for withdrawal of occupation forces. Rather, they should be phased out gradually and occupation should be terminated only after it has been determined and agreed that conditions are sufficiently satisfactory to justify termination.
  1. Enclosure to Memo for NSC from Executive Secretary, subject, “Current Strategic Evaluation of U.S. Security Needs in Japan”, dated May 24, 1949. [Footnote in the source text; memorandum not printed.]
  2. Dated May 6, p. 730.