Soviet Foreign Minister Andrei Gromyko sat across from President Carter at the Cabinet table in the White House last Sept. 30. With a sweep of the hand in one of his exaggerated, almost comic gestures, Gromyko declared, "You can fly your air-launched cruise missiles around the world if you like."

This Soviet concession, in return for U.S. concessions on related sea and ground-launched drones, was a mile-stone in the lengthy drive for a new strategic arms limitation treaty (SALT). The Cabinet Room episode in September gave rise to hopes, which proved to be six months premature, that the SALT 11 agreement was at hand.

Compared with the intercontinental ballistic missiles, submarines and heavy bombers, which are the familiar features of strategic arsenals and the central topics for SALT bargainings, cruise missiles are tiny weapons - but they pack a mighty wallop.

The diameter of the standard U.S. air-launched cruise missile under development is about 25 inches, and that of the sea launched cruise missile 21 inches, small enough nearly to place one's arms around, and the length of each weapon is only 2 or 3 times the height of an average man.

The cruise's powerful jet engine is only 30 inches long.

Each of the slender projectiles can be guided to its target with uncanny accuracy by radars and microcomputers that compare the terrain below with programmed information from contour maps. Each cruise missile can deliver a nuclear weapon with more than 5 times the destructive power of the atomic bomb that leveled the Japanese city of Hiroshima in August 1945.

Cruise missiles as strategic weapons are creatures of SALT. They were given impetus by then secretary of State Henry A. Kissinger in 1972, at the time of the SALT 1 agreement, as bargaining chips with the Russians in SALT 11. At the time, the air launched cruise missile (by far the most important version) was a weapon that hardly existed, had no serious role in military planning and was strongly opposed by the Air Force as a competitor to new manned bombers.

From small beginnings the diminutive weapons have taken on a life of their own. The SALT 11 bargaining over them has been intense, both within the U.S. government and with the Soviet Union. The final result is so complex that a single provision of the proposed treaty, on rules for counting air-launched cruise missiles mounted on heavy bombers, is modified by seven U.S.-Soviet "agreed statements" plus three "common understandings."

By U.S. accounts, cruise missiles were not explicitly discussed by former President Ford and Soviet leader Leonid 1. Brezhnev in their November 1974 bargaining at Vladivostok. However, the Soviets immediately claimed, and the U.S. disputed, that air-launched cruise missiles were covered by the Vladivostok limits.

By the time of Kissinger's hard bargaining on SALT 11 in January 1976, cruise missiles were the major concern of the Soviets. In Moscow, Kissinger offered a complicated series of cruise missile limits in return for Soviet restrictions on ballistic missiles. Opposition to the concessions back in Washington blocked Kissinger from carrying the deal to completion.

Cruise missiles were an important factor in the dramatic failure of Carter's initial SALT proposals to the Soviets in March 1977. While proposing deep reductions in the big ballistic weapons at which Russia excels, Carter initially proposed only minor restraints on Cruise missiles, where the United States was far ahead.

The Soviets cried foul. "Is it not the same for a human being to die of a weapon from a cruise missile or a weapon from a ballistic missile?" demanded Gromyko in a news conference.

As the SALT negotiations moved back on track in May 1977, the United States showed willingness to return to strieter limits on ground and sea-launched cruise missiles, which are worrisome to Moscow because they could be based in Europe.

Restrictions on U.S. air-launched cruise missiles became much more difficult, however, when Carter, in June 1977, canceled the B1 bomber and pledged to rely instead on existing bombers armed with cruise missiles to penetrate Soviet air defenses.

Secretary of Defense Harold Brown, who is reported to have been the architect of the decision to kill the B1, was particularly sensitive to limitations on its cruise missile replacement.

In 1976, the United States had agreed to count heavy bombers armed with cruise missiles in SALT 11 sub-limits on multiple-warhead missiles and strategic bombers. Carter's initial March 1977 proposal to the Soviets withdrew this concession, however.

In September 1977, after much internal debate, the United States returned to its original position, but with limits now rearranged so that 120 cruise missile bombers could be deployed without corresponding reductions in other weapons systems. This was close to the number the Pentagon had in mind for eventual use.

The Soviets soon came to realize, one of their negotiators said, that "one innocent-sounding little paragraph" permitting 120 cruise missile bearing bombers could bring down more than 8,000 highly accurate war-heads on the Soviet Union if 70 cruise missile each were placed on wide-bodied jet aircraft, as discussed in U.S. military journals.

In the spring of 1978, therefore, the Soviets proposed that each bomber be limited to no more than 20 cruise missiles. Brown strongly resisted. The Soviets, however, tied U.S. acceptance of limits on the number of multiple independently targetable reentry vehicle (MIRV) warheads on each ballistic missile. Privately, U.S. negotiators had to concede that these were parallel restrictions.

As so often in SALT negotiations, behind the seemingly arbitrary numbers and abstract principles was a portentous issue - in this case, air defense of the Soviet Union. The U.S. air-launched cruise missile is essentially a penetration aid to pierce Soviet air defenses. Without some outer limit on the number of potential war-heads, the Soviets would have no way, even in theory to plan a defense.

The ingenious solution to the numbers impasse is credited to a middle-level official of the Arms Control and Disarmament Agency. The idea, presented by then-arms control director Paul C. Warnke in Moscow in early September 1978, limited the numbers of cruise missiles on bombers on an "average" basis.

This would restrict the number of air-launched cruise missiles to an overall figure (bargained out finally at an average of 28 missiles perplan). But it also would allow U.S. flexibility to deploy some of its cruise missiles on B52s, which are able to carry no more than 20 per plan at the outer limit, and deploy others in greater numbers on potential wide-bodied missile carriers of the future.

When Gromyko came to the White House on Sept. 30. 1978, the time was right for compromises. The time was right for compromises. The Soviet foreign minister accepted the averaging concept, provided that an average number could be agreed on. He agreed to permit tests of any type cruise missile at any range, and offered to allow unlimited range on the deployment of air-launched cruise missiles "around the world if you like."

In return, Gromyko insisted on strict application of the 600-kilometer limit on deployment of ground and sea-launched cruise missiles. These limits are only for three years, the duration of the SALT 11 protocol, during which time these sleek drones will still be under development. "This was an ofer we couldn't refuse," a U.S. policymaker recalled.

Further details of cruise missile deployment, including restrictions on unarmed cruise missiles for reconnaissance and future multiple-warhead cruise missiles, were to engage the negotiators almost to the end.

However, the essential SALT bargain of limitations on Soviet multiple-warhead missiles in return or limitations on American cruise missiles was set in broad outline in the White House [WORD ILLEGIBLE] . 30, 1976, the time was right for compromises. The time