Not SDI nor MAD but MCS

THE situation was this: One superpower was racing ahead with a promising missile defense system. The other superpower was trying to catch up, but its technology was inferior. In quiet times the race in strategic defenses didn't particularly matter. But suddenly one of the world's chronic hot spots exploded into crisis.

Lights burned late in the Situation Room and the Kremlin. Leaders were hauled out of bed, intelligence services went into overdrive, and national military command centers were crisis-staffed. Following standard procedures, Moscow and Washington ordered their strategic forces to higher alert levels. Long-range bombers went on strip alert, missile-firing submarines left port, rocket forces ran preliminary checklists. Strategic planners routinely recalculated the other side's probable strike capacity against the assumed reliability of its own retaliatory capability.

So far, like Berlin 1961, Cuba 1962, Czechoslovakia 1968, Jordan 1970, the Middle East 1973, or Afghanistan 1979. But with one big difference. For the first time in decades one side worried that the other had a significant advantage in any exchange of nuclear weapons. The adversary's missile defenses might not be perfect. But his ability to knock out most of an attacking force had to be prudently assumed.

Leaders of the lagging superpower did not think the other side would necessarily launch its rockets. But they dared not gamble. The increasingly agitated dialogue went like this: ``Shouldn't we wait for better information about what's going on?'' ``Not if they think our second strike is crippled.'' ``But aren't they still deterred?'' ``We can't be sure.'' ``What about the hot line?'' ``If they think it's safe to gamble, THERE'S NO TIME LEFT.'' ``Mr. President, we'd better launch before they do.''

This scenario ``happened'' in a high-level United States government planning exercise several years ago. The participants included four-star generals and top diplomats. It was the only political-military planning exercise of its kind to end in an all-out thermonuclear exchange. Its sobering implication was that if the Strategic Defense Initiative (SDI) process is uneven - if in a crisis one side thinks it is ``ahead'' - the world could face its moment of maximum danger.

In his 1983 call for SDI, President Reagan intuitively sensed the widespread revulsion at the prospect of living indefinitely under the Damoclean balance of terror. His vision was of a morally superior alternative to the strategy of mutual assured destruction (MAD), under which both sides are deterred or commit civilizational suicide.

The threat of retaliation works because of mutual confidence in retaliation. But if that confidence erodes and deterrence fails, the carnage would be beyond history. How then to square SDI's moral appeal - ``killing weapons, not people'' - with the risk of catastrophic instability during the process of developing effective defenses?

The answer lies in a second Reagan intuition: The path to an alternative global security system must be through collaboration, whether parallel or joint, negotiated or tacit. Reagan's recurrent offers to share research results were shortsightedly derided by both left and right. But it is mutual deterrence that has maintained the nuclear peace; it is unilateral efforts to gain an edge that destabilize the situation, whether they be through superheavy missiles, close-in deployments, nuclear war-fighting doctrines - or all-out, one-sided SDI.

The history of technology confirms that laboratory development will continue in both the United States and Soviet Union. The question is how to move ahead in ways that increase rather than decrease everyone's security. In an era of genocidal weapons, crisis stability is the only meaningful test for any strategic doctrine or arms control agreement. The indispensable criteria are time and confidence for leaders of both countries to ride out crises without being stampeded into decisions for which humanity will not forgive them. There is no rational alternative to MCS - mutual cooperation for stability.

Lincoln P. Bloomfield has participated in high-level Washington war/peace games like the one cited here. He served in the White House National Security Council under President Carter and as a State Department official under Presidents Truman and Eisenhower. He is now a political science professor at the Massachusetts Institute of Technology.