MONIMBO is the name of the town in Nicaragua where the wicked plot was hatched in 1980 by the Sandinistas and none other than Fidel Castro himself. The plot's ambitious goal was to foment racial insurrection and create moral decay in the United States, and once you digest that premise you may well go on to enjoy this cautionary novel of international chicanery and deception by Robert Moss and Arnaud de Borchgrave.

On the other hand, if you are one of those moist-eyed dupes who feel that U.S. policy in Central America and the Caribbean is a bit, well, clumsy, then you could be put off by the novel's unashamedly conservative bias. I myself happen to enjoy a rousing tale told by a political reactionary (E. Howard Hunt and William F. Buckley come readily to mind), and if I didn't enjoy Monimb,o as much as I should, it's probably because its newspaperman hero is something of a klutz. Almost, indeed, a dope.

The hero is Robert Hockney, Washington bureau chief of The New York World, who has to cope not only with the usual feeble-minded editors, but also with a scruffy, left-leaning young reporter who lusts after Hockney's job.

Thus far the characters are comfortably familiar. But then, on one of those blue-rinse cruises to Puerto Rico, which Hockney and his wife have taken in hopes of shoring up their shaky marriage, we encounter the man with hair the color of wet straw and pale green eyes -- eyes that fasten on Hockney with a "predatory force." Immediately, we know that this guy is up to no good and our interest picks up.

The man with the pale green eyes turns out to be a killing machine, but we never quite learn whether he does it for money or out of conviction. We do learn that he is a renegade American and a veteran of Vietnam where he presumably learned the murderer's trade (I suspect it will be at least 1998 before superannuation will remove demented Green Berets from fiction).

In San Juan, meanwhile, a right-wing U.S. senator is kidnapped and our hero is awakened in his hotel room by a phone call from the kidnappers who label themselves Macheteros. A fair example of the gee-whiz style the authors employ is found in our hero's reaction: "Then the meaning of the word sank in, and the reporter snapped fully awake. Los Macheteros-- the Machete Wielders--was a name used by one of the most feared terrorist organizations on the island."

Hockney finds the kidnapped senator dead, along with a clue that the green-eyed American whom Hockney met on the cruise ship might have had something to do with it. "Was it possible," Hockney asks himself, "that he had rubbed shoulders with the terrorists without realizing it?"

Well, it certainly is. And from there we plunge into the story that leads from a riot in Miami to near insurrection in Manhattan, both guided by the bearded one in Havana and no doubt his Moscow masters.

As Miami simmers and threatens to boil over, we meet some likeable overworked cops; a cocaine king who owns a bank and sidelines as a double agent for the CIA and Cuba; various whores and other low-life; and through it all our hero keeps pondering just why it is that those who will condemn the Soviet Union "still find romance and hope in Cuba."

Well, maybe--as he himself admits--it's because "a whole folklore has grown up, compounded of tales--many of them true--about the United Fruit Company; coups and assassination plots masterminded by the CIA; America's complicity in shoring up strutting generals and oligarchs." He concludes sadly that "A Third World leader who wanted the American media on his side would be well advised . . . to begin by attacking the United States."

But Hockney's deep distrust of Castro doesn't prevent him from journeying to Havana and falling into an old-fashioned honey trap. First, the wily Cubans slip a drug into his drink and then photograph him in the naked arms of a Cuban lovely. At about this time you begin to agree with Hockney's New York bosses: maybe they should pick someone else to run the Washington bureau.

Finally, we have a communist-inspired traffic gridlock in New York and our hero is instrumental in saving the city from certain disaster. This may well be the first time gridlock has been suggested as a tactical weapon, and it certainly deserves further study.

Unfortunately, this competently plotted thriller is marred by uneven writing and a lumpish hero. For the most part, the story moves along briskly enough, the backgrounds are nicely drawn, and you can either chuckle over the political bias or nod in sage agreement. And although I can easily forgive the authors their tiresome polemics, I find it almost impossible to forgive them for Robert Hockney, chief wimp of The New York World.