STATISTICS DESCRIBING the volume of ther international traffic in illicit drugs tend to have a number effect. They define huge, almost unimaginable quantities of both narcotics and money. For example, in June Colombian drug officials, with help from U.S. agents, seized ther largest cache of illicit drugs ever confiscated in one raid - 574 tons of marijuana that was about to be shipped to the United States. That amount, worth about $200 million wholesale, was enough to make 1 million cigarettes a day for an entire year.

It's no coincidence that that record haul was captured in the remote Colombian province of Guajira. Colombian authorities are literally at war with drug traffickers who have taken over vast tracts of land in the sparsely populated province along the Caribbean coast. Those traffickers are the reason Colombia in recent years has become the major source of marijuana and a major transit point for heroin and cocaine bound for the United States from South American countries. Next month peasants will start harvesting an area of new marijuana plants that is four times as large as the District of Columbia.

The harvest won't go unchallenged. Colombia's revitalized attorney generals office, which recently has seized or destroyed tons of marijuana and made several key arrests, has organized a special strike force to stop it. And Colombia's new president, Julio Cesar Turbay, has signaled his commitment to the anti-drug campaign by urging the continuation of drug-control agreements between Colombia and the United States.

The situation in Colombia repeats the by-now familiar pattern of a developing country trying to rid itself of the corrosive presence of widespread drug production and trafficking. Experience indicates that Colombian authorities, while trying to root out the $1-billion-a-year drug industry, also must attempt to resolve some large related problems. These include 1) bringing the Guajira region under the authority of the central government and including it in national development programs, 2) developing crop-substitution programs for farmers now dependent upon marijuana as a cash crop, 3) building a network of roads and outlets for produce that make legitimate farming possible and profitable and 4) thereby trying to stem the flow of jobless peasants into the cities.

In short, Colombia's war against drugs is at bottom a war for development. That Colombian authorities recognize the problem in these true dimensions speaks well for their determination to attack it.