Given all the questioning and concern about the Strategic Defense Initiative by both Americans and Soviets, it is easy to overlook the good news. The good news is that the US, since March 1983, and the Soviets, since September 1985, are seriously reconsidering the role of strategic defense in the strategic arms equations. Since the 1972 ABM Treaty, the world has had the millstone of mutual assured destruction about its neck -- a situation deemed immoral by many, and precarious by everyone. Now a new age is upon us.
With Mikhail Gorbachev's offer to reduce offensive nuclear arms in trade for the SDI program, both the United States and the Soviet Union have elevated strategic defense as a factor of coequal weight in the arms control and balance-of-terror equations. The questions remaining are: (1) how to include strategic defense without uncontrolled growth in offensive nuclear arms, and (2) how to maintain deterrence during and after the arms reduction process. An answer to both these questons can be obtained by si mply lumping the number of defensive and offensive systems into a total aggregate, equal for both sides, in effect combining elements of the ABM Treaty and SALT II to produce a new SALT III. Under such an arrangement, both sides would have to make an allocation of resources between offensive and defensive systems, within an overall ceiling. Having agreed to this equation, the next step would be to periodically reduce the aggregate ceiling to numbers that are more acceptable to the moralists and affordable b y the taxpayers.
The practical effects of such a linkage of offensive and defensive systems in a new SALT III would be the following: First, the SDI program would have a rational basis for continuation. Without a planned utility in the long-range strategy of the US, the SDI program will have little appeal to the American taxpayer, and will continue to raise questions among our allies.
The second effect of a SALT III offensive-defense linkage is that there is created a basis for dealing with launch-under-attack issues, accidental launch crises, uncertainties in verification, and even third-country threats. Each superpower could allocate resources toward defensive systems to deal with such matters, up to a limit imposed by the aggregate ceiling and the country's own sense of its security needs.
The summit is an ideal occasion to start the process of reduction. Harry A. Gieske, Silver Spring, Md.
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