`Weapons of Ill Repute'

WEST GERMANY no doubt was embarrassed by US disclosures that a German chemical company, Imhausen-Chemie, has helped Libya outfit the huge chemical plant in the desert - a plant that Washington insists is intended to manufacture chemical weapons. That probably accounts for Bonn's snappish denials, which roiled relations between the two countries for several days. Now, after studying the evidence behind the US allegations, Bonn acknowledges ``indications'' that Washington's claims are accurate.

This is not the first time West German companies have been implicated in the proliferation of ``weapons of ill repute.'' Since the early '80s, the US has repeatedly pressed Bonn to probe the dealings of a company believed to be smuggling ``heavy water'' and other nuclear-weapons materiel to India and South Africa, which have not signed the Nuclear Nonproliferation Treaty.

Last week the West German government announced plans to tighten its export controls over products and technology necessary to produce nuclear and chemical weapons, and to stiffen penalties for violators. This is a welcome step, if Bonn follows through. The tests will be in the severity of the sanctions adopted, and also in the vigor with which Germany investigates and, if warranted, prosecutes offenders.

Although West Germany may have been more negligent than other countries in allowing this sort of trafficking to occur, it is not alone. Businessmen from Belgium, Italy, Switzerland, and other nations also have been implicated in trading that contributes to the spread of mass-destruction weapons. The governments of all the industrialized countries must redouble their efforts to curb this deadly trade.

Among other things, all these countries, including the United States, need to enact harsher commercial and criminal penalties for violations of export controls. Even in countries that have been fairly energetic in enforcing controls, the wrist slaps that pass for penalties do little to deter unscrupulous profit-seekers.