President Bush's announcement this week that the United States would forswear the use of chemical weapons "for any reason," including retaliation - if an international agreement to ban such weapons can be reached - is a welcome one.

The president took the encouraging step in hopes of accelerating negotiations currently under way in Geneva seeking a global ban on all chemical weapons.This marks a change in the U.S. position. Previously, the administration had wanted to hold back 2 percent of its chemical arsenal as a kind of hedge against others violating any pact. But asking all others to abandon chemical weapons while keeping some of our own in reserve is hardly a compelling selling point.

Bush urged other countries to echo the U.S. commitment to a destruction of all poison gas within 10 years of a negotiated treaty and urged the 40-nation conference on disarmament to do whatever is necessary to wind up its deliberations by the end of 1991. If this timetable seems slow, keep in mind that the 39-nation negotiations in Geneva have been plodding along since 1968.

Bush said that the gulf war had demonstrated the fact that "unscrupulous regimes" could "threaten innocent populations" as long as horrifying weapons exist.

It is true that the recent apparent end of superpower rivalry has reduced both the threat of European war and the use of chemical weapons. But by their nature, such weapons are relatively easy and cheap for smaller countries to acquire.

Reaching an international agreement that will cover everyone, including brutal regimes like the one run by Saddam Hussein in Iraq, will not be simple.

Yet if the world can agree to outlaw all chemical weapons - and the Soviet Union is in full accord - any cheaters would be small-time and presumably would think twice about defying a global ban.

Considering the vile, indiscriminate and terroristic nature of chemical weapons, the president's goal to totally eliminate them has to be enthusiastically applauded.

But any agreement between nations on the issue must be truly international in scope in order to be meaningful and acceptable.