The U.S. draft treaty on ballistic missile defenses introduced in Geneva last month incorporates the language of the December summit. It says that each superpower should adhere to the 1972 Anti-Ballistic Missile Treaty "as signed" {news story, Jan. 23}.

This wording makes irrelevant much of the controversy and public debate centering on the "correct" interpretation of the secret negotiating record or on differing understandings expressed during the Senate ratification debate following the signing of the ABM Treaty. The phrase "as signed" obviously confines attention to the written words of the treaty itself.

But the treaty text clearly supports the administration's "broad" interpretation that SDI testing is permitted without any restriction. Paragraph 2 of Article II, which defines ABM systems and components "for the purpose of this treaty," states that ABM systems and components "include those which are (a) operational; (b) under construction; (c) undergoing testing; (d) undergoing overhaul, repair, or conversion; or (e) mothballed." No other categories are given or suggested.

This listing can be recognized as exhaustive and complete; it clearly refers only to 1972 technology, covering all its possible states. Had the drafters meant to cite the five categories merely as examples, they would have -- or should have, as competent lawyers -- added "but not limited to" after the word "include."

The "equally authentic" Russian version of the ABM Treaty does not translate "include" by the most direct term, but curiously uses instead the quite unambiguous otnosyatsya, which means "refers to." In the absence of any qualifier, such as "among other," there is no question that the Russian version also covers only 1972 technologies. Thus the ABM Treaty does not apply to exotic SDI technologies, which were then in the early research stages. S. FRED SINGER Arlington