NINETEEN-NINETY-FIVE is shaping up as a seminal year in world affairs - perhaps the most important since the Berlin Wall came tumbling down in 1989.
Several developments are converging that promise to determine the way nations will view their security and the weapons of mass destruction they possess.
The outcome will either be a planet that is more dangerous or an unprecedented step toward creating what one expert calls a ``durable world order.'' The catalysts:
* The emergence of a tier of nations that have the know-how to produce nuclear, chemical, or biological weapons. Historically subordinate to the great powers, this group of 30-plus countries, from Kazakhstan to Argentina, is poised to play a far more influential role on the world stage.
* Waning confidence in institutions that have helped maintain peace since World War II - including the ``great power'' nations of the US, Britain, France, Russia, and China in general, and the United Nations in particular, which have faltered in the face of Serbian aggression in the former Yugoslavia.
* Uncertainty surrounding the future of arms control. By coincidence, agreements to limit nuclear, chemical, and biological weapons come up for review or ratification next year in what promises to be the most important examination ever of global efforts to control these nonconventional weapons.
The interaction of these events, says Brad Roberts, editor of the Washington Quarterly, will constitute a ``unique moment in world affairs.''
If the technically empowered states ``can be kept firmly involved in the international effort to prevent the militarization of conflicts, to control armaments, and to promote the cooperative resolution of common problems, the international community will have gone a very long way toward putting in place essential ingredients of a durable world order,'' Mr. Roberts writes in the current issue.
``But if they drift away from these efforts, the consequences could be profound:'' dissension among the big powers, greater risk of local conflict, and the end of collective security operations like ``Desert Shield,'' the massive international force mobilized in 1990 to repel Iraqi aggression in Kuwait.
Containing the spread of nonconventional weapons will be harder now than it was during the cold war, experts say. Then, the world was dominated by superpowers that had a strong incentive to limit regional competition and whose security guarantees, in many cases, did away with the need for their allies to build nonconventional weapons.
Containment has also become harder because of the steady erosion of technical constraints, which has made it easier for less-advanced nations to develop nuclear and other nonconventional capabilities.
Advances in computerization have helped. So has a more open world trading system, which has made stemming the flow of high technology equipment across international frontiers harder.
As John Holum, director of the United States Arms Control and Disarmament Agency (ACDA), notes, the technical constraints that have prevented many nations from building nonconventional weapons in the past are weakening because the materials and know-how needed to build them are now so widely disseminated.
That puts a premium on constraining the demand for these weapons, he says, by building a stronger, more credible nonproliferation ``regime'' or set of arms-control agreements. If that goal is achieved, developing nations might be persuaded to continue to entrust their security to such a regime.
But ``if they think the great powers aren't serious,'' Mr. Holum warns, ``countries once confident that their neighbors weren't going to develop [nonconventional] weapons may think their neighbors are going to do so, so the whole thing could unravel.''
Experts say war is not the only risk. States could use their nonconventional weapons to gain leverage - for example, to veto a joint-security operation. No US president would be eager to rush troops to the Gulf to protect Middle East oil supplies if Iraq had a demonstrated ability to attack them with nuclear, chemical, or biological weapons.
``The potential for a much more dangerous world is enormous if we don't have the strength of this regime,'' Holum says. Forty states have the technical capacity to build nuclear arms. At least 25 have the potential to build chemical and biological arms.
The ability to produce weapons has spread even more widely than the weapons themselves. In 1945, only four countries outside the developed world produced military equipment, Roberts notes. Today, about 40 do. Nuclear expertise is also widely disseminated.
Whether the years-long effort to slow the spread of nonconventional weapons gets a needed boost in 1995 will depend on at least three factors, experts say.
First, developing nations will have to be reassured that collective security is still possible in the post-cold-war era. Their confidence has been shaken by the failure of the UN and NATO to counter Serbian aggression in Bosnia, much as confidence in the League of Nations was shaken in the 1930s when it failed to respond to Italian aggression in Ethiopia.
Solid US leadership
Second, developing nations will have to be reassured that the US is intent on playing in the post-cold-war era the kind of leadership role it played in the era after World War II.
``If ... the United States comes to be perceived as a status-quo power and unable to look after anything but its own narrow self-interest - as it did after World War I - international interests will suffer,'' Roberts says.
Third, the nonnuclear states will have to be convinced that the nuclear states are making good on pledges, written into the 1968 Nuclear Nonproliferation Treaty (NPT), to slow the arms race and cut nuclear arsenals.
A convincing step was taken earlier this month in Budapest, when the United States and Russia exchanged documents ratifying the first strategic arms limitation treaty, START I. The ceremony put the treaty into force, paved the way for ratification of START II by the US Senate and Russian Duma (lower chamber), and paved the way for the eventual beginning of negotiations on START III.
START I and II will slash US and Russian nuclear arsenals by two-thirds.
Another litmus test of the good intentions of the nuclear powers will be progress in talks on a treaty to forbid all nuclear blasts. The US dropped its opposition to the test-ban treaty last year, but France and China still oppose it.
The NPT is the lynchpin of global nonproliferation efforts and will come under review in April in New York. The treaty prohibits all but five existing nuclear nations - the US, Russia, France, Britain, and China - from acquiring nuclear weapons. Three countries that have not signed the NPT - Israel, India, and Pakistan - are believed to be capable of building nuclear weapons or have already built them.
The five declared nuclear states will press for an indefinite and unconditional extension of the NPT. To win the day in New York, they will have to make a much stronger case that the nonnuclear states are more secure without than with nuclear weapons - a logic that states such as Ukraine and Argentina, which have voluntarily given up nuclear programs, already embrace.
``They provide a powerful example for other countries,'' Holum says. But not enough of an example, say other experts, who point to the erosion of support for the notion that a monopoly by the five nuclear states ought to be preserved.
Many nonnuclear states favor a series of fixed short-term NPT renewals, which would provide them with greater leverage in future conferences if they deem that the nuclear powers are not disarming fast enough.
Also in 1995, parties to the Biological and Toxin Weapons Convention will seek to strengthen compliance provisions, a step needed if the BWC is to survive review in early 1996.
On the line next year as well is the Chemical Weapons Convention (CWC), which was signed in 1993 and bans the development, production, stockpiling, and use of chemical weapons. Sixty-five nations need to ratify the treaty, but most are waiting for the US to act. The issue is not high on President Clinton's list of priorities and may face opposition in the new GOP Congress. ``If the US sits this one out we're looking at another League of Nations,'' says Michael Krepon, president of the Henry L. Stimson Center in Washington, referring to the US refusal to enter that body after World War I.
Washington Quarterly's Roberts notes other dangers of US inaction.
``If the NPT is given only weak endorsement in April, the CWC languishes, and the BWC remains devoid of compliance mechanisms, the next decade may well witness a broad diffusion of these weapons, a redistribution of military power away from the advanced industrial countries [that are] highly interested in stability'' and regional arms races, he writes.
If the pacts are ``well-tended and strengthened,'' he adds, ``the international community will have the essential tools for beginning to work more productively on the proliferation problem.''