Sensible U.S. officials have been swimming against the riptide of media attention and the consequent flood of expectations that engulfed the semi-summit. They have stressed that this was the first chapter -- the preface, really -- of a story on the scale of "War and Peace" or, perhaps it would be more appropriate to say, "Don Quixote."

But it actually may have been the fourth act of a three-act play. Between the signing of SALT II in the summer of 1979 and this winter, the arms control process may have sputtered out.

That is unalarming. The process has been sterile, coinciding, through 16 years, with an unprecedented Soviet buildup. Kenneth Adelman, director of the Arms Control and Disarmament Agency, notes that in the years of most intense "dialogue," 1970-76, there were five summits, and the Soviet-sponsored conquest by communists of five countries -- South Vietnam, Laos, Cambodia, Mozambique and Angola. (Ethiopia and Afghanistan followed in the next two years.) If arms control is -- as Jimmy Carter said and Richard Nixon seemed to believe and Ronald Reagan may be coming to believe -- the "centerpiece" of U.S.- Soviet relations, it is a purely ornamental centerpiece.

More than 12 years have passed since an arms control agreement was ratified by the United States. The inequalities of SALT I ignited the skepticism that was to prevent ratification of SALT II. SALT I limited but neglected to define, "heavy" missiles. At Vladivostok, the runup to SALT II, the two sides agreed to certain numerical ceilings, but neglected to decide whether cruise missiles or the Soviet backfire bombers counted against the aggregate.

When arms control enthusiasts are described as destitute of achievements but not of certitude, they reply, with certitude, that the 1972 ABM treaty was a great achievement. It effectively killed, at least for the United States, ballistic missile defense. But the Soviet Union is brazenly violating it with a radar installation so gargantuan that it probably had to be planned before the ink was dry on the treaty.

However, it is arguable that a traditional aim of arms control -- improved safety through more stable deterrence -- may be a byproduct of the exhaustion of the arms control process. The argument is as follows:

SALT I and SALT II did not "limit" arms. Those agreements were snapshots of the evolving strategic balance. But arms agreements do not halt an arms race. Rather, they redirect competition toward uncontrolled areas of weaponry. (Sen. Pat Moynihan notes that the naval treaties of the 1920s gave rise to the pocket battleship -- the punch of a battleship crammed into a smaller hull.)

Today, certain weapons are apt to be unlimited because of verification difficulties. They are apt to be small because improved accuracy makes a large payload unnecessary for the destruction of many military targets. Being smaller and mobile, they are hard to count and keep track of. But the qualities that make these weapons hard to control with verifiable arms agreements also make them hard to destroy with a disarming first strike. So, as Adelman says, mobile ICBMs and cruise missiles may be less verifiable but more stabilizing because they ease the fear that in a crisis a nation must "use them or lose them." Such precarious "stability" at high force levels is far from ideal, but maybe the best that can be hoped for in relations with a Soviet regime bent on amassing offensive power.

A French observer says the Soviet Union's tactic is to do what it wants to do and use negotiations to stop what the United States wants to do. Today the Soviet Union wants to magnify its advantage in offensive systems while stopping U.S. progress toward a strategic defense.

But Ronald Reagan is an American in every fiber of his being. That means he believes that something is technically possible until it is proven otherwise. And he is a moralist. Both characteristics fuel his belief in the possibility and desirability of some defense against ICBMs -- the desirability of "defending lives, not avenging lives."

Note the word "some." Reagan, as is his wont, has oversold strategic defense, suggesting that it can provide an impermeable "shield" that could in no place be overwhelmed by the multiplication of Soviet offensive systems. A sufficient argument for strategic defense is that it would provide some real defense (the Soviets could not be sure how much) to some of the U.S. retaliatory capability. Thus it would enhance deterrence by radically complicating the calculations and multiplying the uncertainties of any Soviet leader contemplating a first strike.

Given the barrenness of the arms control process, it is odd that an objection made against strategic defense is that such defense might make arms control agreements unattainable. But an oddity of our age is this: the sort of persons most eager for ratification of the meaningless treaty "outlawing" genocide are apt to be ardently opposed to strategic defense systems. But such systems would move us away from deterrence based on the threat to incinerate millions of civilians, a strategy that is, strictly speaking, genocidal.