Foreign Relations of the United States, 1964–1968, Volume XXVII, Mainland Southeast Asia; Regional Affairs

150. Memorandum From James C. Thomson, Jr., of the National Security Council Staff to President Johnson¹

Washington, December 28, 1964.

SUBJECT

• United States Relations with Cambodia

Here is where U.S. relations with Cambodia now stand in the wake of the New Delhi talks.

1. The Basic Problem:

Sihanouk deeply fears Cambodiaʼs traditional enemies, the Vietnamese and the Thais; his fears of South Vietnam are compounded by recurrent border violations that result from the war. Sihanouk also believes that the U.S. will fail in South Vietnam; and regardless of the outcome in Vietnam, he believes that good relations with Communist China are the key to Cambodiaʼs survival as an independent state.

Improved U.S. relations with Cambodia are therefore tightly tied to the struggle in South Vietnam: if the U.S./GVN position improves—and if the Vietnamese are forthcoming on border problems and certain other bilateral issues—Sihanouk will probably decide that friendly relations with the U.S. would make sense for Cambodia. The best we can expect from him, however, is a somewhat more neutral left-leaning “neutralism”.

2. U.S. Attempts at Conciliation:

Our relations with Cambodia began to deteriorate severely in the autumn of 1963 as the Vietnam situation entered a period of deterioration. Sihanouk suspected U.S. backing for his Cambodian political opponents in Thailand and Vietnam, the “Khmer Serei”; he was convinced that the CIA planned the assassination of Diem and Nhu; and he assumed that a large U.S. presence in Cambodia might lead to his downfall through CIA plots. In November–December the Cambodians requested an end to all U.S. aid, called for a Geneva conference on Cambodian neutrality, and closed their Embassy in Washington.

While resisting Cambodiaʼs periodic calls for such a conference—mainly because of our desire to avoid a Geneva conference on Vietnam—we have taken several steps toward conciliation with the Cambodians since January 1964.

• —We encouraged Philippine efforts to mediate our dispute, but these efforts failed.
• —We offered to send Dean Acheson as a confidential emissary to Sihanouk, but the offer was publicly spurned.
• —We made proposals for four-power talks in response to Sihanoukʼs initiative, but our proposals were rejected.
• —We supported the UN Security Council Commissionʼs recommendations for the establishment of UN civilian observers in Cambodia, but Sihanouk denounced these recommendations.
• —We supported a sympathetic new Ambassador (Randolph Kidder) to re-open the dialogue, but Sihanouk refused to receive him.

Most recently, in November, we proposed that representatives of both countries meet in a neutral nation to discuss our differences. To our surprise, the Cambodians accepted at once, and the New Delhi conversations were held in December.

3. The New Delhi Talks:

Our negotiators—Ambassadors Bonsal and Koren—met with the Cambodian representatives on December 8th; although the atmosphere was relatively friendly, the talks were adjourned inconclusively on December 17th.² (Sihanouk had simultaneously authorized negotiations in Peking which were equally inconclusive; these talks will be resumed in January.)

The key to the failure of the Delhi talks was the Vietnam situation: the Cambodians concentrated on their grievances against South Vietnam; we replied that we could not speak for the GVN—with whom the Cambodians refuse to talk.

Four major Cambodian demands dominated the talks, each involving aspects of the Vietnam war and, inevitably, Cambodia-GVN relations: 1) that the U.S. accept responsibility for all the incidents on the Vietnam border; 2) that the U.S. provide substantial compensation for these incidents (Cambodia suggested a “face-saving” device by which the U.S. would provide a “gift” of 100 heavy tractors and bull-dozers in lieu of such compensation); 3) that the International Control Commission be expanded, at U.S. expense, to control the entire length of Cambodiaʼs borders; and 4) that the U.S. Government publicly absolve Cambodia of all responsibility for aiding or harboring the Viet Cong, and that we pledge to refrain from any further public or private (i.e., newspaper) accusations along these lines.

4. Where To Go From Here:

The chief obstacle to improved U.S.-Cambodia relations remains the bad condition of Cambodiaʼs relations with South Vietnam. Here the major and most difficult problem is the frontier. But there are a number of lesser issues which could be resolved with relative ease.

Ambassador Bonsal believes that the door remains open to further talks with the Cambodians, although further border incidents could close that door. But such talks will be useless unless we can press the GVN to be forthcoming on Cambodiaʼs lesser grievances.

State is now working along the following lines:

a) As soon as the immediate political crisis in Saigon is resolved, we will strongly urge the GVN to take action on the lesser grievances. This should include renunciation by the GVN of Diemʼs groundless claim to two useless offshore islands; a proposal to exchange prisoners; and an offer of compensation for damages to certain Cambodian villages on the South Vietnam border. We will also urge that the GVN publicly accept certain mutually satisfactory maps as the correct designation of frontiers (there is no dispute about the maps, only about where the markers should actually be located on the ground).³

b) Once the GVN has indicated its good faith by taking these initiatives, we should approach the Cambodians for further bilateral talks in Phnom Penh on the frontier problem. If the atmosphere had improved, the GVN might participate in such talks.

c) On the specifics of frontier control, we might re-examine Cambodiaʼs proposal for an expanded ICC but stress that the costs must be shared by all the Geneva powers, including Communist China. (Although we should expect renewed demands for re-convening the Geneva conference as a result of this proposal, our legal experts are convinced that the ICC could be expanded on the frontiers without resort to a conference.) We might also offer Army Mapping Service assistance in the clear demarcation of the border under the terms of an aerial mapping agreement that we negotiated with the Cambodians in the mid-1950ʼs.

d) We should consider new efforts to persuade the Thai and Vietnamese Governments to cease their support of the dissident Khmer Serei exiles whose clandestine broadcasts enrage Sihanouk.

e) Meanwhile, we are continuing to stress to our military in Saigon the urgent need to take special precautions to avoid further incidents on Cambodian side of the border.

We are now pressing State to develop on an urgent basis the specifics of such a general approach to the Cambodian problem. We shall keep you informed of Stateʼs progress.⁴

JC Thomson Jr.

1. Source: Johnson Library, National Security File, Country File, Cambodia, Vol. III, Memos 8/64–6/65. Secret.
2. Bonsal and Korenʼs memorandum to Harriman, January 4, 1965, reporting on their talks is in Department of State, Central Files, POL CAMB–US.
3. Bundy wrote the following note next to this paragraph: “Chet [Cooper] & Jim [Thompson]: this.”
4. Bundy wrote the following note next to this paragraph: “OK, Iʼd like.”