167. Intelligence Report Prepared by the Central Intelligence Agency's Directorate of Intelligence1
US–USSR Offensive Strategic Force Balance: Evolution and Measurement, 1965–1976
The period since 1965 has been one of dramatic change in the strategic balance between the US and USSR and in the perception of that balance. It was widely recognized in the mid-1960s that the strategic [Page 774]balance was clearly in favor of the US because it led by such a wide margin in every simple numerical measure of strategic offensive power. Seeking to redress the imbalance, the Soviets began to improve and enlarge their forces, and by the mid-1970s they had achieved a rough strategic parity.
In the late 1960s and early 1970s many important technological innovations incorporated into both the US and Soviet nuclear arsenals complicated the perceptions of the strategic balance. Simple measures, such as the number of strategic nuclear delivery vehicles, were no longer as accurate a reflection of the strategic balance as they had been when one side had a clear margin in each category. Improvements in accuracy, throw weight, multiple warheads, and the capability to destroy hard targets required the introduction of a variety of more complex measures.
The Soviets, because of the dramatic growth in their intercontinental attack forces since 1965, now lead the US in several single measures of strategic power:
—number of delivery vehicles
—on-line equivalent megatonnage
—on-line missile throw weight
—lethal area for soft targets—i.e., the area that could be subjected to an overpressure of 103.4 kilopascals (15 pounds per square inch) or more by their on-line force.
The US, on the other hand, continues to lead in:
—number of on-line missile RVs
—number of on-line missile RVs combined with bomber weapons
—on-line missile K factor, a measure of a missile’s capability against a hard target.
Since the early 1970s it has become increasingly difficult to determine which country holds a strategic advantage.
[Omitted here is the Report, which addresses factors determining evolution of U.S. and Soviet strategic forces, measuring the strategic balance, and future considerations.]
- Source: Washington National Records Center, OSD Files: FRC 330–79–0049, 320.2 Strategic (Aug–Dec.) 1976. Secret; [handling restriction not declassified].↩