Like the famous George Santayana quote goes, "those who cannot learn from history are doomed to repeat it." And thanks to a cache of documents released by George Washington University's National Security Archive project, the American people are learning just how close their country came to sparking a devastating nuclear conflict with Russia and China back in the 1960s.

The Lyndon Johnson-era "Single Integrated Operational Plan" (or SIOP) laid out how the US military would carry out a retaliatory (or preemptive) nuclear strike with the objective of eliminating the Soviet Union and China as "viable" societies, and the USSR as a "major industrial power." The "overkill" plan intended to wipe out 95% of its top-level targets with loss of human life as the primary metric for success. No version of the SIOP has ever been fully declassified, meaning that the documents released by GWU offered the first complete picture of the US's Cold War-era nuclear-defense plans. While the US military had created the first version of the SIOP in the early 1960s, the version published by GWU is from 1964.

Here's a summary of the new information included in the documents.

The Joint Staff review of the SIOP-64 guidance includes new information on nuclear war planning: The SIOP guidance permitted "withholds" to hold back strikes on specific countries. Recognizing the reality of Sino-Soviet tensions, it would be possible to launch nuclear strikes against the Soviet Union without attacking China or vice versa or to withhold strikes from Eastern European countries, namely Albania, Bulgaria, and Romania Priorities for Task Alpha targets: At the top of the list of the most urgent target categories were: heavy and medium bomber bases, unprotected ICBM sites (silos did not shield Soviet ICBMs until early 1964), and IRBM/MRBM [intermediate range/medium range ballistic missile] sites. For the top priority "Task Alpha" targets, the SIOP-64 guidance set an even higher damage expectancy of 95 percent, "a high degree of probability of damage." Thus, overkill continued to be baked into the SIOP. Yet, because nuclear planners based their assessments of damage on the blast effects of nuclear explosions, they did not take into account the further devastation caused by fire effects, especially in urban areas. The purpose of one of the retaliatory options was to destroy the Soviet Union as a "viable" society because it targeted Soviet military forces (conventional and nuclear) plus strikes on urban-industrial targets – Task Charlie.

The 1964 plan didn't include specific casualty projections, while an earlier version of the SIOP projected that the planned strikes would have killed 71% of the residents of major Soviet urban centers and 53% of residents in Chinese population centers. Meanwhile, estimates from 1962 predicted the death of 70 million Soviet citizens during a "no-warning US strike" on military and urban-industrial targets.

But even the most comprehensive plan couldn't guarantee that the retaliation by the USSR and China wouldn't lead to an "unacceptable" level of US casualties. This fear was the primary driver of the US-Soviet arms race, as GW points out in its analysis.

The urgency given to counterforce targets and the availability of preemptive options added momentum and instability to the U.S.-Soviet strategic competition. Washington identified more Soviet nuclear installations for the target lists, which then boosted the Pentagon’s requirements for more nuclear warheads.

Turning our attention to the present day, it's tempting to dismiss these documents as relics from a bygone era. But this simply isn't true. The latest US Nuclear Posture Review, released in late February, revealed that the US is still prepared to launch nuclear strikes against China and Russia in response to both nuclear and non-nuclear provocations. The plan embraces a hawkish approach to military cooperation with both countries and anticipates myriad threats in the military expansionism currently being embraced by both China and Russia. Given this paranoid outlook, it's hardly surprising that Russia earlier this year unveiled plans for a revamped nuclear arsenal - while China's navy last year surpassed the US's fleet in size. Of course, these actions will be perceived as threats by the US...and the vicious cycle will continue until one side capitulates, or both sides plunge headlong into a full-scale nuclear conflict.