The most important development in 1964 was the Chinese explosion of a nuclear device on October 16. China also halted the decline of its air forces and increased the number of MIG-19 Farmer aircraft. Of the estimated fifteen surface-to-air missile sites in China, thirteen were confirmed as SA-2 sites by the end of 1964.
The nuclear explosion and the continued missile developments, prompted a CINCPAC assessment that China was assigning high priority to the development of modern and prestige-type weapons. The missile program was seen as being broader in scope and more advanced than previously thought.
During the year, CINCPAC intelligence also completed the detailed analysis of Chinese and North Korean forces begun in 1963. The study significantly influenced military planning and CINCPAC’s assessment of Chinese intentions. One aspect concerned Chinese perceptions of the U.S. willingness to use nuclear weapons in the region. According to CINCPAC:
- “Chinese Communists hoped that the U.S. would forego a strategic nuclear retaliation for fear of world opinion. Although they might be faced with tactical nuclear weapons in the Southeast Asian area, the Red Chinese considered that the advancing columns, shrouded by vegetation and darkness, would present few lucrative targets. More importantly, the Chinese believed that the Southeast Asian did not wish to be liberated by nuclear weapons.” Overall, China thought that if the U.S. used nuclear weapons in Southeast Asia, the Chinese losses would probably not be great.”
As a result of the analysis, the JCS in June directed CINCPAC to prepare a contingency plan against a Chinese large-scale aggression in Southeast Asia, South Korea, or elsewhere. CINCPAC responded by developing a unilateral plan according to which U.S., allied, and friendly forces would conduct limited war contingency operations against China, North Korea, and North Vietnam to forestall or halt a large-scale aggression by China or its allies. The new plan, designated OPLAN 39-65, was very flexible. It could be executed as a separate campaign or as part of an overall Pacific Strategy. The concept envisioned four situation where large-scale Chinese aggression might become imminent or be directed against the following areas:
- Taiwan — By China;
- South Korea — By China and North Korea;
- Southeast Asia — By China and North Vietnam;
- Southeast Asia and South Korea — By China, North Vietnam, and North Korea.
OPLAN 39-65 was promulgated in September and continued through the remainder of the year. By the end of 1964, Annex E (which concerned nuclear operations) was still under preparation.
These plans and operations are described in more detail in the selected pages from the 1964 CINCPAC history provided below:
Commander in Chief, U.S. Pacific Command, “CINCPAC Command History 1964,” April 23, 1965. Only selected pages. Partially declassified and released under FOIA. (1.77 MB)