An ugly idea hovers over our deliberations on SALT: that the Soviets are perfectly capable of looking nuclear war in the eye, that they are not deterred as we are by the threat of tens of millions of casualties on both sides, that they actually have it in mind to fight and win a nuclear war.

This is customarily said hald in out-rage (that the Russians are beasts, to take this cynical view) and half in envy (that they have the guts to face up to a prospect from which Americans shy).

Intellectually, of course, the idea that the Soviets think nuclear war is winnable tends to serve SALT. The more bloody-minded the Kremlin, the more urgent it becomes to apply whatever restraints SALT holds. But politically the idea is muder. It suggests that the Soviets are orientally oblivious of casualties, bent on violence, inherently aggressive, i.e., exactly the sort you would not want as a SALT partner.

To some people the notion of the kremlin's readiness to fight and win a nuclear war is an unexplored emotional premise. To others, it's deduced from hardware, like big multiple-warhead missiles, that the Soviets are deploying and developing, although a fair-minded person has to grant, I think, that the Kremlin could make the same deduction from hardware we're deploying or developing. For still others, it is proved from Soviet texts.

Typically, just this week Defense/Space Daily quoted Air Force Gen. Alton Slay's remarks on "three books put out by U.S. intelligence based on interpretation of writings by Soviet military planners."

Said Slay: "The thing that came through loud and clear . . . is the fact that they had not only though about nuclear war but believe that they would win the war . . . They are filled with war-fighting abilities to bring on an end to the war in a nuclear holocaust of any size. They look at a nuclear weapon in the same fashion that we look at an 8 inch round that is nonnuclear. It is a weapon. That came through to me and it scared me . . . "

Slay's book review seems to me the Pentagon's familiar primitive budget-time line. But he is correct in asserting that the Soviet military talks a lot about fighting and winning a nuclear war. Should the marshals not be taken word?

The best answer I have found comes from scholar-diplomat Raymond L. Garthoff, formerly a SALT team member and currently ambassador to Bulgaria. Writing from 30 Years of expert and policy-wise familiarity with the Soviet military scene, Garthoff offered his own views last summer in Harvard's International Security magazine.

He demonstrates from both the Soviet literature and from Soviet policy in the SALT negotiations that at least since SALT began in the late 1960s, the Kremlin has accepted that the superpowers' rough strategic balance provides for mutual deterrence. That is, the Soviets figure to pursue their often-unfriendly and unhelpful aims while avoiding nuclear war.

Gartoff addresses directly what troubles gen. Saly and so many others: "It is not accurate, as some Western commentators have done, to counterpose Soviet military interst in a 'war-fighting' and 'war-winning' capability to a 'deterrent' capability; the Soviets see the former capabilities as providing the most credible deterrent, as well as serving as a contingent resort if war should nonetheless come."

In other words, to talk about fighting and winning a war doesn't prove intent or readiness. It is military talk, it is meant to serve morale, it arises from the requirement even the Pentagon feels to make plans, it reveals a felt need for a rationale for building up forces.

Garthoff further shows that Soviet belief in mutual deterrence (rather than war-fighting) and in the unacceptablilty of nuclear war is maintained not only for public show and export but in deliberations of the Soviet General Staff. He does this by citing a number of issues of the General Staff's confidential journal Military Thought - a rare and impressive source.

His conclusion is that the Soviets do not have a nuclear glint in their eye such as to make SALT a snare and a delusion. Rather, he suggests, "the principal problems in arms control accommodations are not due to differing operative aims' of the two sudes, but to differing perceptions, to suspicions, and to the difficulties of gearing very different military forces and programs into balanced and mutually acceptable strategic arms limitations," He's exactly right.