Foreign Relations of the United States, 1951, Korea and China, Volume VII, Part 1

INR–SE Files¹

National Intelligence Special Estimate

secret
SE–1

[Washington,] January 11, 1951.

International Implications of Maintaining a Beachhead in South Korea²

Problem

To estimate and enumerate the advantages and disadvantages of holding a UN beachhead in South Korea.^*

Estimate

1. The maintenance of a United Nations beachhead in South Korea would have the following major strategic and military implications for the United Nations and the United States:

a. Maintenance of a beachhead would have the following military advantages:

(1) Full attainment of the stated Communist objective in Korea would be denied.

(2) The loss of US military prestige which would result from a withdrawal would be avoided.

(3) The continued commitment of major Chinese Communist forces in Korea and Manchuria would restrict the Chinese Communist capability for rapid consolidation of China, for large scale expansion in mainland Southeast Asia, and for resisting invasion elsewhere on the mainland of China.

(4) The Soviet Union would be obliged to continue the supply of material in support of Communist forces in Korea.

(5) The Communist forces would be denied an additional operational base against Japan.

(6) In the event that large scale operations against China become necessary, Korea would be favorable for joint UN–US ground operations because:

(a) The superior air and sea power of the UN forces could be brought to bear effectively against the numerically superior ground forces;

(b) Chinese Communist attrition would be relatively high in the confined battle area in Korea;

(c) The beachhead would provide an operational base that would tie down large numbers of Communist forces, could be used to mount subsequent operations in Korea, and could be used to support operations elsewhere in the Far East in the event of a general war with China.

b. The maintenance of a beachhead would have the following military disadvantages:

(1) A critical proportion of the US Army and substantial proportion of US naval and air resources would be committed in the area, thereby reducing immediate US capabilities for building up forces elsewhere.

(2) A considerable drain on US military resources would be imposed not only in the support of US forces in Korea, but also in the complete logistic support for Republic of Korea forces and the major part of the logistic support for all other United Nations forces in Korea.

(3) UN forces within the beachhead would be subjected to constant attrition (and in the event of overt Soviet intervention, danger of annihilation).

(4) The continued deployment of the Army forces of the Far East command in Korea would leave Japan more vulnerable to hostile invasion.

(5) The US would be required to continue its support of several million Korean refugees.

2. A UN beachhead would have the following short-term international political and psychological effects:

a. There would be an avoidance of the great loss of prestige to the UN and the diminution of confidence in the US that would follow a withdrawal.

b. The maintenance of a beachhead would place stresses on the UN coalition stemming from increased fear of general war, provide continued Communist propaganda opportunities arising from a conflict between the West and Asiatics, and continue European concern over the diversion of major US military strength to the Far East.

c. The Chinese Communists would be prevented from achieving complete success in Korea and the beachhead would provide a continued symbol of UN determination to resist aggression.

d. Most Far Eastern countries would react favorably to the maintenance of a UN beachhead. In Japan, maintenance of a beachhead would be particularly advantageous with respect to negotiations leading toward a Japanese peace treaty. Those countries in Southeast Asia vulnerable to an early Chinese Communist attack, however, would be apprehensive about the possibility of a general war with China while UN forces were involved in Korea, and Indonesia and Burma particularly would favor a withdrawal.

e. In South Asia, India would react unfavorably to the maintenance of a UN beachhead because of Indian hopes of reducing the possibility of a major war and because of a general inclination to sympathize with Asiatics as against Westerners; Pakistan would react favorably to any evidence of US military strength. In the Near and Middle East, the maintenance of a beachhead might salvage to some degree US military prestige among Iran and the Arab states; Greece and Turkey would oppose UN withdrawal unless it were part of a broader plan to attack Communism at its source, or unless they were convinced that Western Europe or the Near East were immediately threatened.

f. The reaction in Western Europe would be influenced on the one hand, by an intensification of the fear that prolonged and inconclusive fighting in Korea would result in the extension of hostilities elsewhere and on the other, by concern lest the UN fail in a major effort to contain Communist aggression.

g. Latin American reaction would be favorable.

h. It is unlikely that Soviet policy will be significantly modified by a UN decision to maintain a beachhead in Korea.

1. Files of National Intelligence Special Estimates retained by the Bureau of Intelligence and Research.
2. According to a note on the cover sheet: “The intelligence organizations of the Departments of State, the Army, the Navy, the Air Force, and the Joint Staff participated in the preparation of this estimate and concur in it. This paper is based on information available on 8 January 1951.”
3. In the event of full-scale Soviet intervention in Korea, it is estimated that it would be impossible for UN forces to maintain the beachhead. [Footnote in the source text.]