WHEN North Korea refused to let UN personnel Inspect its clandestine nuclear installations. it threw into crisis the system of oon-military constraints on the development of nuclear weapons that for half a century has enforced the nu clear powers' monopoly on mass destruction.

The US government has decided that these constraints — secrecy, export controls, and the Nuclear Nonproliferation Treaty — may no longer be adequate to meet what it views as unprecedented threats to American security.

In response, it has promulgated a new doctrine of ''counterproliferation''.

Last December. then-Secre tary of Defense Les Aspin announced a 'Defense Counter proliferation Initiative' to add "protection" to the ""preventive" political measures of the existing nonproliferation regime. Aspin proposed "a drive to develop new military capabilities" to shield against and. if necessary, to attack perceived threats from un named nations and groups in the Third World

Such military capabilities would include a wide range of weapons systems, from theater missile defenses to precision guided non-nuclear munitions capable of destroying hardened

underground installations.

Officials at the State Department are reportedly cool to the idea, concerned that unilateral military strategies could undermine the multilateral political regime so laboriously constructed over the past few decades. And NATO allies were wary when asked to endorse the concept at their .January summit.

In response to this growing concern. Ashton Carter. Assis tant Secretary of Defense for International Security Policy and the Clinton Administrations leading advocate of coun-lerprollferation. downplays the military option, arguing that it is Just one dimension of the issue and is merely Intended to reinforce traditional multilateral diplomacy

But many kinds of clandestine arms productions are impossible to target and the eco nomlc and political costs of pursuing an aggressive military option could easily outweigh the dangers posed by a nation possessing one or two rudimentary nuclear devices

Financial costs alone could easily run into tens of billions of dollars This Is a point not lost on the still-powerful Star Wars lobby within the ’Pen tagon the arms Industry and Congress, where counterproliferation technologies have been embraced as the best hope for securing new funding

since the Strategic Defense Initiative Organization was disbanded last year

Deploying a sophisticated theater missile defense system in Japan to defend against a putative threat from even a primitive North Korean bomb could cost at least US$8 bll lion. Meanwhile, the Interna tional Atomic Energy Agency (IAEA), the world community's principal organisation for monitoring • clandestine nuclear programmes thoroughout the world, continues to be suffering from a chronic lack of funds. It has a budget of only US$60 million a year, and have even been forced to cancel In spectlons.

Many specialists in non proliferation both in the United States and the rest of the world criticise the demili tary counter-proliferation at tack.

Some predict that the first effect of promoting a new doctrine of unilateral military offensive action against poten tial proliferators might be to scuttle next year's Nonproliferation Treaty Review Conference and thus undermine the entire nonproliferation regime.

Others say counterprolif eratlon would needlessly antagonise both the smaller nu clear powers and many non nuclear nations and produce a political and perhaps military backlash. Still others believe that such criticisms are overblown, maintaining that the principal thrust of US counterproliferation efforts is not to attack would be prollf erators but simply to prepare US forces to fight effectively in environments where prolifera tlon has already occurred.

However these questions are answered, once assertive military options are introduced into the mix of politics and diplomacy that has effectively restrained proliferation up to now. they could all too easily take on a momentum of their own. generating yet another self-perpetuating cycle of threat and counter threat

With the inexorable spread of technologfral capabilities to new nations and the rising risk that essential expertise and materials will leak to rogue state* and terrorist groups out the desperate chaos resulting from the breakup of the Soviet Union, the possibility of fur ther proliferation la all to real

Only when the great powers themselves derisively reduce their still-vast stockpiles o| nuclear arms and other weapons of mass destruction will other nations cease trying to gain access to these totems of ultimate power