253. Memorandum From the President’s Assistant for National Security Affairs (Kissinger) to President Nixon1


  • Cambodia Options

The Situation

Cambodia’s President Lon Nol has written asking immediate U.S. aid in arming Cambodian forces to a total of 410,000 (Tab A).2

North Vietnamese and Vietcong forces are nearing Phnom Penh. They have moved with surprising ease against the poorly organized, ill-equipped and ill-trained Cambodian forces. It is not certain that they intend to take over the country but they may soon be in a position to do so. The Cambodian forces of 35,000 Army and 40,000 Paramilitary is being expanded rapidly—addition of 30,000 is now underway, but it will take time for them to become effective. Fuller background was covered in my memorandum of April 22.3

Our Chargé in Phnom Penh, though perhaps excessively alarmist, reflects the concern of other foreign embassies in recommending we be prepared to evacuate American personnel from the city.4

The Consequences of Cambodia’s Fall to the Communists

Cambodia’s fall to the Communists would have the following seriously adverse consequences:

  • —In the immediate aftermath of a Communist takeover in Cambodia there would be a profound psychological shock in South Vietnam.
  • —Over the longer run, South Vietnam would be completely surrounded by hostile territory.
  • —The heretofore limited covert operations of Communist forces from Cambodia into Vietnam will become overt and much larger.
  • —The Communists could send in North Vietnamese units and units formed of Vietnamese residents of Cambodia. They could also form a Guerrilla movement of Cambodian ethnics in South Vietnam. The new situation might not have immediate military consequences, but would certainly begin to tell in six months or a year.
  • —Communist forces in South Vietnam, particularly in the Delta area, could count on obtaining all the food and military supplies they need, whereas now they suffer some shortages.
  • —Vietnamization would be impossible to carry out. The South Vietnamese government and army could not preserve itself against pressure from all sides without a very large continuing presence of U.S. forces.5
  • —Our negotiating position would be complicated.
  • —In the rest of Asia, there would be a feeling that Communism was on the march and we were powerless to stop it. Thailand in particular would be subject to greater pressure.

What We Are Doing

The following measures have been undertaken or are planned:

  • —The ARVN has undertaken several ground operations against Communist forces in Cambodia since the change of Government. Those have been fairly extensive, and have included South Vietnamese air support. One such operation which was just completed involved 2,500 men and lasted for two days. Penetration was 3 or 4 kilometers.
  • —An operation on a larger scale is pending, however. This will involve a multi-division effort in Svay Rieng with full air and artillery support. The initial thrust will be 7–8 kilometers, but will be joined by other forces moving to cut off the entire Parrot’s Beak. It is hoped that this particular operation will cause the Communists to draw off the combat units which they are now employing against Phnom Penh in order to defend their base camps. The operation has received general approval from both the ARVN and MACV drafters, but still needs final approval from the ARVN joint general staff.
  • —U.S. operations have been essentially B–52 strikes. (Tactical air operations on a small scale have been permitted for some time in the extraction of special forces teams from missions in Cambodia.) Strikes have been conducted at a rate of one or more per week against Communist base camps just opposite the Vietnamese border, mainly in III and IV Corps.
  • —This week strikes are planned for targets opposite the Central Highlands in II Corps, the Angel’s Wing area of III Corps, and in the zone between III Corps and IV Corps southwest of the Parrot’s Beak.
  • —These raids have been effective in destroying supplies and dislocating troop concentrations, but have not seriously interfered with Communist military plans. If continued during the major ARVN operation mentioned above, or during similar operations of this scale, the disruptive effectives could be much greater.
  • —One U.S. tactical air operation is now planned: Operation Patio, which will cover an area 20 miles deep into Cambodia from the Vietnamese border, about 60 miles south of the tri-border area. It will consist of tactical aircraft and forward air controllers for artillery fire, and will be backed up with teams on the ground.
  • —U.S. arms shipments to Cambodia have consisted of 1,500 AK–47s, which were airlifted into Phnom Penh as of 12 noon Washington time April 22. 1,300 more will be sent in the same way tomorrow. A 1,000-man pack of U.S. arms and equipment will also go into Cambodia shortly.
  • —Several thousand more AK–47s will be readied and shipped over the next week.

Our Immediate Options

The Lon Nol government is better than any alternative at this point. Given the likely consequences of its fall, it is in our interest to give it the moral support it needs by evidencing willingness to help and to help its struggle by giving what material assistance we can.

  • Military Assistance The Cambodians have asked for quantities of equipment far in excess of what they could use effectively or what could be delivered in time to be of help in the present situation. They now primarily need light weapons, ammunition and radios.
  • —Delivery of even small quantities quickly will have an important psychological effect and bolster Cambodian morale though they will not necessarily change the unfavorable military balance.
  • —There are two ways we can help:
  • —Open delivery—this would enable us to move large quantities in quickly. But the risks are not worth it.
  • —Use CIA 1000-man packs—These are available now and each fully equips a unit. They could be moved rapidly to equip three new regiments the Cambodians are forming and be delivered without directly showing our hand. If it is disclosed we would have the excuse that we had wanted to limit our commitment.
[Page 866]

I recommend that for now we stick to the CIA packs.6 It will not meet all of the Cambodian’s requests but will do enough to have some military impact in the Phnom Penh area and give a morale boost.

Approve CIA Packs

Prefer Open Delivery

Military Operations in the Border Region

Attacks against North Vietnamese/VC sanctuaries near the South Vietnam border will tie down enemy forces needed for their protection, disrupt his logistics support and take some pressure off the Cambodians. Attacks can be made by cross-border operations, tactical air, or B–52s or a combination of these.

Cross-border operations—There are three levels.

  • —Shallow—2–3 miles in depth of the type now conducted by ARVN forces of brigade size supported by their own artillery and tactical area. These attacks harass the enemy and tie down some of his forces but have been insufficient to limit his offensive operations in Cambodia.
  • —Deeper Penetrations—These would extend up to ten miles into Cambodia and would require forces numbering up to a division supported by tactical air and artillery. They would attack bases and headquarters now beyond reach disrupting enemy logistical support and sowing confusion which would take some pressure off Cambodia. Such attacks limited in depth or duration would be responsive to Lon Nol’s desire that they go no deeper.
  • —Massive operations—of multi-divisional size supported by artillery, tactical air and B–52s seeking to permanently deny the sanctuaries to the enemy. This would seriously disrupt enemy logistical support and capability to operate either in Cambodia or against South Vietnam. Lon Nol would at least publicly criticize such attacks, however, and international repercussions could be serious. It would involve greater U.S. involvement and could provoke North Vietnamese reaction against Phnom Penh.
  • Air Attacks—either by tactical air or B–52’s could damage enemy bases and concentrations which could not otherwise be reached. They could be independent of or in support of cross-border operations. They would have disruptive effects on enemy operations in Cambodia and Vietnam but would have their maximum effort in conjunction with ground operations. They risk disclosure, however, with potential adverse international and domestic reaction.
[Page 867]

I recommend, in the present situation, deeper penetrations of division size but not permanent investiture of the sanctuaries. The penetrations would be conducted by ARVN divisions supported by their own artillery and tactical air and by U.S. cross-border artillery, tactical and B–52 strikes on specific targets. To further assist the ARVN forces, I recommend U.S. forces be deployed in the border area to relieve ARVN forces needed for these attacks.

I recommend you approve deeper ARVN penetrations with U.S. cross-border artillery support, tactical air and B–52 strikes.

Khmer Krom and Khmer Serai Deployment—There are 3,500 Cambodian ethnics forces now in South Vietnam equipped and trained. They are part of the Special Forces. Lon Nol asked for them and Ambassador Bunker recommends that four battalions of them be airlifted to Phnom Penh with their equipment. They would strengthen Cambodian forces at Phnom Penh and have an important desirable psychological effect in Cambodia. They lack logistical support, however, and we will have to arrange to provide it. This can be done through the South Vietnamese.

I recommend we approve airlift of the Cambodian Forces to Phnom Penh as soon as possible.

I have enclosed summaries of the recommendations of Ambassador Bunker (Tab B)7 and the JCS (Tab C).8

  1. Source: National Archives, Nixon Presidential Materials, NSC Files, Box 506, Country Files, Far East, Cambodia, Vol. III, 10 April 1970–23 April 1970. Top Secret; Sensitive.
  2. Tab A was a retyped copy of telegram 593 from Phnom Penh, April 21; see footnote 4, Document 240.
  3. Not printed. (National Archives, Nixon Presidential Materials, NSC Files, Box 506, Country Files, Far East, Cambodia, Vol. III, 10 April 1970–23 April 1970)
  4. Telegram 582 from Phnom Penh, April 21. (Ibid., NSC Institutional Files (H-Files), Box H–073, WSAG Meeting, Cambodia, April 21, 1970)
  5. Nixon highlighted this paragraph and wrote the following note: “K. put this in speech if I have to make one.”
  6. At the end of the memorandum, Nixon wrote: “OK, all plans.”
  7. Tab B was a retyped copy of Document 251 and a summation of the recommendations it contained.
  8. In Tab C the JCS recommended providing M–1’s to equip Cambodia’s 85,000 person army, developing plans for attacks by division-size RVNAF forces on enemy positions in the sanctuaries, rescinding the current restrictions on U.S. forces on the border to provide logistic and artillery support for RVNAF forces engaged in Cambodia, and developing plans for employing Cambodian “ethnics” in the Special Forces. These recommendations were taken from a copy of Document 244, which was also attached at Tab C.