The envelope, please.

The award for Most Preposterous Argument of 1985 (no use waiting; this one is untoppable) goes to an argument for continuing U.S. compliance with the unratified SALT II treaty even after Dec. 31, when it would have expired anyway. The argument is: To abrogate SALT II limits would send a bad "signal" to Moscow at a "delicate moment" in the arms control process.

How can something dead be delicate? And what could be worse than the signal this president would send by continuing compliance with a treaty that a Democratic-controlled Senate refused to ratify in 1979 -- a treaty candidate Ronald Reagan denounced as "fatally flawed"?

When the Trident submarine Alaska enters service this autumn, the United States will exceed SALT II limits on MIRVed missiles, unless a Poseidon submarine is scrapped. But arms control has become such a virulent superstition that preservation of an unratifiable treaty is considered crucial.

Newsweek solemnly -- nay, apocalyptically -- "reports" that abandonment of even the expired, unratified SALT II would be an "ominous" threat to "the whole fragile web of restraints on the nuclear-arms race that have been negotiated since 1963."

Now, "fragile" hardly describes "restraints" that have coincided with the unprecedented Soviet buildup. Newsweek's warning is woven -- talk about fragile webs -- primarily from four unnamed sources. Given the caliber of their arguments, their desire for anonymity testifies to an endearing capacity for embarrassment.

Newsweek reports that "one U.S. official bluntly says": "The question is whether we begin to unravel arms control in the hope that it can be woven back together -- or whether to demolish it." Blunt? Unintelligible. Anyway, if everything arms control has accomplished can be demolished by treating an unratifiable treaty as what it is -- a dead letter; if arms control depends on complying with an agreement that the Soviets are violating wholesale; if so, what, precisely, is the arms control edifice that will tumble down?

Pointing with pride when there is nothing to be proud of can be amusing. A flack for a losing basketball team announced that his squad's record was 19-0 in games they led at the end of the fourth quarter. That flack belongs in Geneva; he is a born arms controller. He, perhaps, could point with pride to SALT II, under the "restraints" of which the Soviets have added 4,000 warheads and can add several thousand more without violating its "limits."

Newsweek reports that a "senior Russian diplomat" says new agreements in Geneva will be impossible unless the United States continues to comply with SALT II. But there has been no progress in Geneva since January, and the Soviet regime insists progress will be impossible until President Reagan abandons his Strategic Defense Initiative, which he will not do. So the Soviet diplomat is merely adding a redundant insolence to the arms control farce.

Newsweek reports that "one British Foreign Office official" says: "It is one thing to put more pressure on the Russians and quite another to abandon the treaties altogether." Yes, but it is a third thing to adhere to a treaty you denounced in 1979 and that you say the Soviets are violating promiscuously. Leaving aside the nice point of whether you can "abandon" an unratified and expired treaty, this is clear: If this president -- the denouncer of SALT II, the documenter of Soviet violations of it -- continues to comply with it, Gorbachev will reasonably conclude that this president is unserious about compliance -- and perhaps about everything else.

A "senior administration official" tells Newsweek this is "the most important foreign-policy decision the President is ever likely to make." True, but not for reasons arms controllers give. The president must deal with the Soviet regime regarding the Middle East, Afghanistan, Central America. If he caves in concerning SALT II, and tries to cover his cave-in with a tricky, transparent, cosmetic maneuver, the Soviets will dismiss him as all noise.

The cosmetic solution would be to mothball but not dismantle a Poseidon. This would be a secondary failure of nerve about the primary failure of nerve. It would collapse the president's credibility by showing him unable to justify continuing compliance but afraid to brave the reflexive wrath of the arms control lobby.

Secretary of State George Shultz is off on the charade of "consulting" allies, who will urge continued compliance because the arms control charade is the opiate of their masses. But a task of diplomacy -- and of a Great Communicator -- is to explain courageously the need to act unfashionably.

In 1979 arms control was, as always, fashionable, but many senators courageously opposed SALT II. The Foreign Relations Committee, a nest of doves, approved it by only a single vote. The Armed Services Committee rejected it. If Ronald Reagan, who helped stop it then, will not abandon it now, three years stretch ahead like a dangerous Sahara.