THOSE FOR AND AGAINST the administration's plan to begin producing chemical weapons after a 13-year moratorium agree that the Soviet Union has an impressive CW capability (though it may not have more weapons than we do). They agree that Soviet defensive abilities--protective gear, decontamination equipment, combat training--are superior to our own. They agree that U.S. policy should continue to renounce first use of these weapons. And they agree that our goal should be a complete and verifiable ban on the production, stockpiling and use of chemical weapons.

Most of them also agree that without a complete chemical warfare ban, the Western alliance needs some chemical offensive capability to deter a Soviet chemical attack. This is not because of the theoretical magic often ascribed by military analysts to the ability to "retaliate in kind." Nothing is to be gained from responding in kind to any particular type of attack if you have a more effective weapon. And because modern protective gear makes a soldier invulnerable to chemical attack, practically anything is a more effective than a chemical weapon against protected troops.

Rather, the need for some U.S. chemical weapons arises precisely because of this unique characteristic: chemical weapons' sole use (other than to kill unprotected civilians) is to force the enemy to don his protective gear. This slows him down, impedes communication and makes all phases of fighting as difficult for him as for you.

This is where proponents and opponents of the proposed new weapons split. Opponents point out that the existing CW stockpile is perfectly adequate to accomplish this limited military role. The United States and its allies need only fire occasional chemical rounds in order to keep Soviet attackers operating in their protective gear. Supporters of the new weapons quibble about the age and amount of existing chemical weapons, and point out some of their limitations, but they do not refute this crucial practical argument.

But the administration says it "cannot overstress" its conviction that the United States needs the new binary chemical weapons as "a prod to get the Soviets to negotiate seriously"--a multi-billion dollar bargaining chip. But the chemical arms control talks stalled because they raise the most difficult problems of verification and compliance. New weapons are hardly likely to scare the Soviets into more acceptable positions. The binary program should be voted down.