WASHINGTON — THE containers marked humanitarian supplies sat unclaimed for months in the airport customs warehouse in Maribor, in the former Yugoslav republic of Slovenia. But they did not hold food or clothing.
When officials finally looked inside in August 1993, they discovered 120 tons of infantry weapons, including 10,000 Chinese-made assault rifles, 750,000 rounds of ammunition, rockets, and explosives.
The Muslim-led Bosnian government eventually admitted ownership of the arms. Had they been delivered, they would have joined more than $2 billion in light weapons believed to have evaded the United Nations arms embargo that year.
The hardware slipping into Bosnia is symbolic of a massive global trade in light weapons that is becoming a growing concern in foreign capitals around the world.
While attention often focuses on big-ticket items -- tanks, jet fighters, and ships -- small arms sold by governments and black marketeers are increasingly fueling ethnic, religious, and political conflicts worldwide.
The trade in light weapons has long existed. But as religious and ethnic hatreds supplant cold-war tensions as major sources of international instability, concerns are now being voiced about the unrestrained nature of the trade -- and its impact on global security.
''This is something that people ignored during the cold war. We are just paying attention to it for the first time,'' says Natalie Goldring of the Washington-based British American Security Information Council.
The council last week held the first of several international conferences to establish a worldwide research network to study the dynamics of the small arms trade and its political and economic effects on regional stability.
''We want to gather the information necessary to come up with pragmatic, coherent policy proposals to limit this trade,'' explains Ms. Goldring.
Lora Lumpe, of the Federation of American Scientists' Arms Sales Monitoring Project, says there is a pressing need for such an effort: ''The new security paradigm now is regional stability and regional conflict. If you look at regional conflicts, an absolute common denominator is the presence of large quantities of small arms.''
Small arms range from pistols, rifles, and grenades to machine guns, antitank and antiaircraft rockets, mines, and mortars. They are the most basic building block of an army's arsenal as well as being cheap and, therefore, cost-effective. Copies of the famed Russian-designed AK-47 Kalashnikov, the assault rifle of choice worldwide, have been known to sell in parts of Africa for as little as $6.
These weapons are also low-tech, durable, easily transported and concealed, and widely available. As such, they have become the muscle behind the emergence of some of the world's new post-cold-war states and major instruments of ethnic or religious zealotry.
From Bosnia to Cambodia, Nagorno-Karabakh to Somalia, and even to gangland turf battles in US cities, these weapons are fueling rivalries and adding daily to the estimated 40 million lives claimed by conventional arms worldwide since World War II. By comparison, 200,000 people died in history's only atomic bomb attacks.
But even though small arms are to blame for most of the world's post-World War II bloodshed, there have been no concerted attempts to restrict the trade by leading powers, including the United States. For one thing, stopping the flow of millions of rifles would be far more difficult than controlling the export of a few jet fighters.
For another, there is money to be made: As of 1994, almost 300 companies in more than 50 countries were making small arms and related equipment, according to the United Nations Institute for Disarmament Research. That represents a 25 percent increase in known producers since 1984. China, with at least 16 factories, is believed to have the world's largest small-arms industry. The United States ranks fifth.
Aaron Karp, an arms trade expert at Virginia's Old Dominion University, says there is no reliable mechanism to track global light weapons sales and transfers since most are secret. But he estimates they account for 10 to 15 percent of all government-to-government arms transfers, or as much as $2.5 billion annually. Paramilitary groups spend another estimated $2.5 billion to $3 billion a year on small arms, he says. Other experts estimate the total annual trade at up to $10 billion.
These estimates do not include the value of light-arms smuggling by soldiers, such as occurred in Chechnya, where Russian troops sold weapons to their Chechen rebel foes. Nor do they include weapons stolen from military and police forces. For example, the Pentagon estimated in 1985 that up to $1 billion in equipment was disappearing every year from its arsenals.
During the US-Soviet rivalry, scant attention was paid to the light-arms trade as the two superpowers and their allies sold or gave away prodigious amounts to political proxies or favorite causes, many of them in the developing world.
Government policies primarily regulated transfers of ''big ticket'' military hardware, such as tanks, jets, and ships, to other governments. International arms-control efforts focused on nuclear, chemical, and biological weaponry.
''Arms policies were not really about conflicts,'' says Mr. Karp. ''They were about managing political relationships.''
Following their rapprochement, Washington and Moscow began accelerating efforts to reduce weapons of mass destruction. The global economic downturn and overbuying during the 1980s, meanwhile, have discouraged many arms purchasers, such as Middle Eastern states, from acquiring new major weapons systems.
In contrast, many experts believe the light-arms trade is soaring. One reason is that many of the countries the cold-war rivals transferred arms-making technologies to are no longer restricted by political considerations in their trading. So some sell to just about anyone.
Another factor, these experts say, is that prices have dropped. Former East-West adversaries have created a glut of weapons by selling stocks they no longer need at rock-bottom prices.
''Proliferation has gotten worse simply because countries in the former Warsaw Pact and the NATO pact have begun dumping their arsenals on the free market,'' says Joost Hiltermann of the Washington-based Human Rights Watch Arms Project.
A US official agrees that the argument has a ''certain amount of logic.'' But he adds that because of the lack of an international tracking system, there is no ''empirical evidence'' that the small arms trade is growing.
There is little dispute about the considerable US contribution to the worldwide small arms deluge. Successive US governments in the 1970s and 1980s transferred billions of dollars in infantry weapons to ''friendly'' third-world states and cold-war proxies, including rebel groups in Afghanistan, Nicaragua, and Angola. Much of this hardware is now available on the world market, including Stinger antiaircraft missiles supplied to anticommunist Afghan rebels during the Soviet occupation of Afghanistan.
''The role that the US played in flooding the world in small arms through covert arms transfers to the third world was considerable. This has created flows of weapons that are still circulating,'' says Ms. Lumpe. Even US troops have come under fire by US-supplied small arms, including some of the $151.5 million in equipment transfered between 1950 and 1993 to Somalia.
Current US trade in light weapons is not known. In 1981, former President Reagan pushed through Congress legislation abolishing an annual government disclosure of the quantity and value of every official and commerical foreign arms transfer. Now only major arms sales are made public.
In February, President Clinton approved new guidelines for US conventional-arms transfers. While the policy is classified, the administration sees arms sales as a ''legitimate instrument'' of US foreign policy ''deserving [of] US government support.''
The new policy, it says, ensures the security needs of the United States and its allies. Arms transfers will be judged case by case and there will be no transactions that could be ''destabilizing and threatening'' to regional security, says the administration.
But critics contend that the policy is designed to enhance an administration goal of maintaining the country's overwhelming dominance of the more than $30 billion international arms market. The US share is more than $22 billion.
These critics point out that, for the first time, the new policy formalizes the use of US embassies and agencies to market American military hardware. It also mandates that protecting US jobs must be considered when export applications are reviewed.
The US official, speaking on condition of anonimity, concedes the policy could have been ''a bit stronger'' on light weapons transfers. But citing the policy's anti-proliferation safeguards, he insists that ''where the rubber meets the road will be on individual sales.''
Overall US arms-sales policy is under review by a presidential advisory board. The panel now is considering what areas to focus on, and the US official says that America's role in the global light-arms trade ''could be one of them.''
But he says that the government could take only ''marginal'' steps to curb the flow of light weapons into regional hot spots, arguing ''there is no room for a broad-gauge policy.''
''We are talking about weapons that are perfectly legitimate for national self-defense,'' he says. ''I don't see much possibility for well-intentioned generic restrictions on exports of light weapons.''
Most experts agree that a broad international effort to limit the small-arms trade would be difficult to achieve, except for a possible ban on land mines. But they contend that modest steps could be taken to restrict the trade and alleviate some of the misery and destruction it facilitates.
More than 90 members of Congress are cosponsoring legislation that would establish a ''code of conduct'' for US arms sales. The bill, opposed by the administration as an infringement on presidential decision-making, would ban sales to foreign buyers who violate human rights and engage in aggression against their neighbors.
The bill would also require recipients to cooperate in efforts to curb the world arms trade, including a UN program in which countries register major transactions. While light-arms deals are currently exempted, the UN registry program could be expanded to include them, experts say.