By George P. Shultz, William J. Perry, Henry A. Kissinger, and Sam Nunn
As long as there has been war, there have been efforts to deter actions a nation considers threatening. Until fairly recently, this meant building a military establishment capable of intimidating the adversary, defeating him or making his victory more costly than the projected gains. This, with conventional weapons, took time. Deterrence and war strategy were identical.
The advent of the nuclear weapon introduced entirely new factors. It was possible, for the first time, to inflict at the beginning of a war the maximum casualties. The doctrine of mutual assured destruction represented this reality. Deterrence based on nuclear weapons, therefore, has three elements:
- It is importantly psychological, depending on calculations for which there is no historical experience. It is therefore precarious.
- It is devastating. An unrestrained nuclear exchange between superpowers could destroy civilized life as we know it in days.
- Mutual assured destruction raises enormous inhibitions against employing the weapons.
Since the first use of nuclear weapons against Japan, neither of the superpowers, nor any other country, has used nuclear weapons in a war. A gap opened between the psychological element of deterrence and the risks most leaders were willing to incur. U.S. defense leaders made serious efforts to give the president more flexible options for nuclear use short of global annihilation. They never solved the problem, and it was always recognized that Washington and Moscow both held the keys to unpredictable and potentially catastrophic escalations.