As Colombia's 38-year civil war careers toward a showdown between Latin America's largest rebel group and government forces backed by the United States, it is worth asking where the rebels got their some of their vast supply of weapons.

Part of the answer may come as a surprise to those unfamiliar with the murky world of arms dealing: A substantial shipment of guns was air dropped to the Revolutionary Armed Forces of Colombia, or FARC, as the result of a 1999 deal involving two men, each with his own connections to U.S. intelligence agencies.

One was Vladimiro Montesinos, then the Peruvian spy chief, who was on the CIA payroll for years. The other, Sarkis Soghanalian -- a permanent U.S. resident nicknamed the "merchant of death" by some U.S. officials -- has a long history of conducting covert arms trafficking.

How did people with ties to U.S. intelligence agencies become involved in a deal that provided weapons to a narco-insurgency, which the United States has devoted more than $1 billion, as well as military advisers, to defeating? Soghanalian has said he was duped -- that he believed the arms were destined for Peruvian forces. Montesinos, now in jail in Peru facing charges of arms and drug trafficking, isn't talking. Whatever happened, no one denies that the deal ended up putting 10,000 Kalashnikov rifles in the hands of the FARC.

The transaction is more than a commentary on the war in Colombia, Peruvian politics or Soghanalian's business practices. It should also serve as a cautionary tale to members of the Bush administration who want to make it easier for U.S. intelligence agencies to deal with unsavory characters in the name of national security. At the end of the day, their agenda is not necessarily our agenda, their motives might be very different from our own, and they can end up threatening our security down the road.

Soghanalian is a familiar name in intelligence circles. The Turkish-born Lebanese citizen, who has lived in the United States for more than 20 years and who has offices in Paris, Amman and Miami, has been in the arms business for more than three decades. His clients have included various international pariahs, ranging from Nicaragua's Gen. Anastasio Somoza to Iraq's Saddam Hussein.

How the FARC became another recipient is a complicated story that emerges from court records, public statements and interviews with officials here and abroad. In 1999, Soghanalian and a Miami-based partner, international financier Charles Acelor, arranged to ship Kalashnikovs from Jordan. According to U.S. law enforcement officials and Peruvian court documents, about 10,000 of them were air dropped in crates fitted with parachutes over the FARC's jungle stronghold during four flights between March and August 1999. This was enough for the 17,000-member FARC to engage new recruits and keep its veterans amply stocked.

This fresh supply of arms helped the FARC intensify its military attacks recently. It has shot down U.S.-supplied helicopters, hijacked a Colombian plane and kidnapped a senior Colombian senator running for president. In response, on Feb. 21, the Colombian government abandoned cease-fire talks and launched a military assault to take over the Switzerland-sized zone held by the rebels. The overwhelming majority of the casualties have been innocent civilians.

Soghanalian has a long history of collaboration with U.S. agencies, including the Defense Intelligence Agency, the CIA and the FBI. He has rented planes to the CIA, helped bust a Lebanese counterfeit operation that was printing $100 bills and served (unsuccessfully) as an interlocutor in attempts to free American hostage Terry Anderson, held in Beirut from 1985 to 1991. Convicted in two separate cases of three felony charges, this gunrunner has nonetheless ingratiated himself with successive U.S. administrations. As a result, his punishment has been mild, when he has been punished at all.

Even if one accepts Soghanalian's explanation that he believed the Peruvian government to be the final destination of the shipment, he may have violated a 1996 law requiring him to obtain a license for such a deal. In fact, he had been prohibited from arms brokering under the earlier Arms Export Control Act after his 1991 conviction for conspiring to sell 103 combat helicopters to Iraq. Moreover, his protestations of ignorance are open to question. We have examined about 500 pages of Peruvian court records and interviewed officials from U.S. Customs, the FBI, and the Jordanian and Peruvian governments. They suggest that Soghanalian took steps to disguise the transaction, including the filing of circuitous flight plans and the arranging of air drops in remote areas, which would seem unnecessary if the customer were legitimate. In addition, it appears he only backed out of the multiphase deal -- which was supposed to include another 40,000 guns -- after it became a public scandal.

We at the Fund for Peace have presented details of this case to federal prosecutors, the State and Justice departments, and U.S. Customs. If the past is any guide, U.S. authorities are used to stepping lightly around Soghanalian's affairs. For his unrelated conviction of defrauding a California bank, Soghanalian was sentenced last year to time served after a U.S. attorney presented the judge with secret documents detailing Soghanalian's "substantial assistance to law enforcement." Similarly, for the 1991 conviction in the Iraqi helicopter deal, Soghanalian was released after serving just two years of a 6 1/2 year sentence because of his cooperation on the Lebanon counterfeiting case.

On Jan. 29, the Commerce Department's Bureau of Export Administration quietly indicated that the 10-year restriction on Soghanalian's ability to export any commercial goods from the United States had expired. Fortunately, the State Department's Office of Defense Trade Controls restrictions applied in 1992 remain in effect. They bar him from exporting defense articles, and have extra-territorial scope.

In 1996, the U.S. Congress -- acknowledging the role that arms brokers play in fomenting conflict and terrorism around the world -- passed an amendment to the Arms Export Control Act. The change was aimed at closing the loophole for offshore arms trafficking by requiring U.S. nationals living anywhere and foreign nationals residing or conducting business in the United States to register and obtain licenses for all arms deals that they transact, whether on or off U.S. soil.

Soghanalian is precisely the kind of person Congress was trying to target. Under the amendment, Soghanalian would have been required to register and obtain a U.S. license for a possible transaction with Peru.

If, as we believe, Soghanalian knew that these weapons were destined for the FARC, which was designated a terrorist group by the United States in 1997, that could be a violation of a variety of U.S. and other nations' laws, including the U.S. Anti-Terrorism Act of 1996.

The United States has long relied upon arms dealers and dubious characters to do its dirty work. In the mid-1990s, Congress tried to scale back this reliance, but its efforts have proved insufficient, largely because the U.S. government has lacked the political will to enforce them. In the wake of Sept. 11, the Bush administration is rolling back the standards. On Dec. 28, President Bush signed the Intelligence Authorization Act, which effectively removes some of the restrictions on CIA recruitment of human rights violators. The 1996 arms brokering amendment has never been tested in court. Without a precedent-setting case, many in our government remain ignorant of its existence, and arms traffickers carry on without being put on notice. Meanwhile, in perfect step, former CIA operative Robert Baer has written a new book extolling the government's need to lie down with more dirty dogs.

But by now Americans should be amply warned about these partnerships of expediency. As the cases of Osama bin Laden and other former U.S. proxies have demonstrated, relying on undesirable people often leads to unintended, and undesirable, consequences -- a phenomenon common enough to merit its own name -- "blowback," in CIA jargon. The danger of using -- and funding -- these intermediaries has far exceeded any utilitarian value they may serve.

To counter the well-armed FARC, the Bush administration is proposing nearly $600 million in counternarcotics training, equipment and other assistance in its fiscal 2003 budget, plus a non-narcotics component of $98 million in training and helicopters to protect a frequently attacked oil pipeline. The human toll is harder for us to gauge since the victims often live in remote areas and do not figure into our national security interests.

As we contemplate a further escalation of our involvement and investment in Colombia's civil war, we have sent a message to Colombia's government: Sever ties with those abusive elements in your country, the paramilitaries, that you use to do your dirty work.

It is high time to heed our own advice.

Kathi Austin is director of the Arms and Conflict Program at the Fund for Peace and the University of California at Berkeley. Jason Felch, a graduate student at UC-Berkeley, is a research intern at the Fund for Peace.