52. Memorandum From the Joint Chiefs of Staff Representative to the National Security Council Review Group (Unger) to the Chairman of the Review Group (Kissinger)1

SUBJECT

  • NSSM–27, US Policy for Korea (U)
1.
(U) Reference is made to your request at the Review Group meeting on 6 February 1970, and to the revised Issues Paper, subject as above, which was provided to the Joint Staff by the NSC Staff on 16 February 1970.2 JCS comments are provided below, along with suggested revisions to the Issues Paper, attached hereto.3
2.
(S) The NSSM–27 paper4 raises the issue of the capabilities of the existing forces now in Korea and the appropriate level of US/ROK ground forces required to defend Korea against the potential threat. The JCS do not concur with the judgement in the Korea Study that 12–14 ROK divisions could hold an attack by North Korea. The current JCS objective for an adequate defense of Korea against North Korea, calls for 21 combat-ready divisions (19 ROK, 2 US). At some risk (which is increasing due to growing obsolescence of ROK equipment) the existing ground forces in Korea (17 ROKA, 1 ROKMC, and 2 US) have been able to deter an all-out attack and maintain a relatively stable situation in a tense environment. These forces are considered capable of stemming a North Korean attack and/or fighting a delaying action against a combined NK/CPR attack while awaiting additional support.
3.
(S) The premise in NSSM–27 that a reduced number of improved and modernized divisions could equate to a somewhat larger number of unmodernized divisions is to some extent valid. However, it must be recognized that there are definite limits to which equipment improvement can offset reduction in force, particularly in the case of infantry divisions. The type of modernization required (high densities [Page 133]of air and ground mobility resources, advanced communications equipment) would be prohibitively expensive to acquire and support. Further, the modernization would be limited by time and the technical capabilities of the ROK. Given the special circumstances in Korea (uneasy Armistice, difficult terrain, and proximity of Seoul to front lines), reductions in ROK ground forces below 18 divisions should not be considered, and substantial improvements should be made to existing forces including ROK air and naval forces. The JCS do not consider the NSSM–27 postures provide adequate funds for essential ROK air and naval improvements.
4.
(S) The JCS believe that withdrawal, now, of US forces would be untimely. Should such withdrawals be directed, the JCS consider that the minimum posture necessary to maintain existing deterrence and stability in Korea is 1-1/3 US divisions and 18 improved ROK divisions, with improvements to the ROK air and naval forces (as outlined in the JSOP) and continued US tactical air support. (The JCS have forwarded a plan for a reduction to 1-1/3 US divisions to the Office of the Secretary of Defense (ISA).) The JCS consider that 1/3 of a US division and 19 modernized ROK divisions would provide this same capability, but believe it would be imprudent to consider this reduction in US forces until the return of ROK forces from Vietnam.
5.
(S) The above represents the JCS view of the military considerations concerning US/ROK posture in Korea. However, proposals for withdrawal of US troops must also address other important factors involved, including political, psychological and economic. US forces in Korea are a symbol of the US commitments to the defense of the Republic of Korea, and in fact to all of Northeast Asia. Any significant or rapid reduction in the US presence could cause anxiety to the Koreans and be regarded (by both allies and enemies) as evidence that the United States had lost interest in meeting its defense commitments in Korea. This would be particularly serious if US reductions were not fully offset by the completion of substantial improvements to ROK forces in advance of any US withdrawal.
F.T. Unger

Lieutenant General, USA
  1. Source: National Archives, Nixon Presidential Materials, NSC Files, NSC Institutional Files (H-Files), Box H–042, Senior Review Group Meetings, Review Group Meeting—NSSM 27 Korea 2/19/70. Secret. Copies were sent to members of the Review Group.
  2. See Document 51. The final report on NSSM 27 was completed on December 19, 1969, and is in the National Archives, Nixon Presidential Materials, NSC Files, NSC Institutional Files (H-Files), Box H–042, Senior Review Group Meetings, Review Group Meeting—NSSM 27 Korea 2/19/70.
  3. The JCS revisions are attached but not printed.
  4. Document 27.