IN STARKLY REVOLTING and heart-rending detail, staff writer Janet Cooke introduced readers of Sunday's editions to "Jimmy's World" -- the story of an 8-year-old, third-generation heroin addict in "a world of hard drugs, fast money and the good life he believes both can bring." So repugnant, depressing and foreign to most people is this morally corrupt "world" of one child in the city that it would be a relief to dismiss this account as an exaggeration or an aberration. But Jimmy's world is not limited to Jimmy at all -- he is just a close-up example of the younger and younger children who are growing up with scrambled values and hooked bodies.

As reporter Cooke writes, "Heroin has become a part of life in many of Washington's neighborhoods, affecting thousands of teen-agers and adults who feel cut off from the world around them, and filtering down to untold numbers of children like Jimmy who are bored with school and battered by life." What makes this all so frustrating is the cold fact that the "world" of these children is not simply the Southeast Washington neighborhood where Jimmy lives, nor is it 14th Street NW, or the East Coast. It is the international world, where -- just like the dealers who move from block to block in this city when authorities try to clamp down -- when a "connection" is severed in one part of the globe, another one takes its place.

When the Nixon administration tried to persuade Turkey to get out of the opium business, Mexican heroin flooded the market; and now the heroin situation in this city, which some authorities say has reached epidemic proportions, is linked to the so-called "Golden Crescent" traffic from Iran, Pakistan and Afghanistan. Complicating any government attempt to cut off these supplies is the fact that the United States has such tenuous diplomatic ties with many of the key parties.

Nothing in the ancient history of the poppy points to any eradication of the international traffic in drugs. But attempts to diminish it cannot begin to succeed either unless they, too, are made on international levels. Where negotiations are possible to exact actions by foreign governments curbing the heroin trade, they should be pursued.

At home, of course, drug addiction programs, campaigns warning of the dangers, law enforcement and some sense of hope for today's children in tomorrow's job market are all factors in the effort. These are tall orders, but unless public as well as official attention is focused on the seriousness of the heroin problem, "Jimmy's world" will be seen by other youngsters as all that there is.