THE NEW BREED By W.E.B. Griffin Putnam. 398 pp. $16.95

IN The New Breed, the seventh novel in his "Brotherhood of War" series, W.E.B. Griffin deals convincingly with two subjects that in the recent past sent middle-class American males scurrying to the ivied bunkers of draft-deferred academe and storming the parapets of the nation's divinity schools -- America's dirty little wars and the Americans who fight them.

It's December 1963 and Colonel Sanford T. Felter, presidential troubleshooter without portfolio, has two pieces of bad news from the hustings for recently elevated President Lyndon Johnson: (1) the South Vietnamese army has a bad case of the coups ("Goddam," grumbles LBJ, "where I came from, when we buy some politician he stays bought"), and (2) the tenuous post-independence tranquility in the new Democratic Republic of the Congo is in danger of evaporating upon the imminent departure of U.N. forces from the former Belgian colony. With respect to the latter, Felter's orders are to keep a back-channels, surreptitious American eye on the situation and make sure the Russians and Chinese keep their surreptitious noses out.

To keep the lid on, Felter beefs up a clandestine Congo contingency plan (code-name Eagle), inserts American Special Forces A-Teams there to gather intelligence on Soviet and Chinese intentions, infiltrates mercenary forces warming up in the bullpen in South Africa in the event they are contacted (and contracted) to put down any revolt in the Congo, and waits for someone to set the inevitable match to the Congolese tinderbox.

As he has done in his earlier novels, which have earned him a loyal and growing following if not mainstream acknowledgement, Griffin, a former soldier, skillfully sets the stage for the big dustup, melding credible characters, a good eye for detail and colorful, gritty dialogue into a readable and entertaining story.

Colonel Felter is a no-nonsense pro with a contempt for bureaucrats such as the CIA Deputy Director ("He thought the man was nothing but a clerk who made it to his Deputy Director's job by doing nothing wrong, and who had done nothing wrong because he had taken no chances"), a sardonic tongue ("Well, it's not much of a secret. Even the CIA knows about it") and the ultimate leverage in getting underlings in gear when he cranks up his clandestine Congo operation ("The minute I suspect you're playing games with us, you'll be on the next plane to Vietnam"). Beat Sanford Felter's sword into a plowshare and he'll use it to clear the fields of fire in front of his machine gun emplacement.

Griffin's accounts of '60's stateside Army life are extremely well done. He nicely captures the relentless, nothing's-ever-good-enough demands of Army basic training from the recruit's perspective ("He and the other inductees . . . had been given a welcoming speech, which included a long litany of what the Army could and would do to anyone who decided to go home, or talk back to a sergeant, or consume controlled substances, or have in their possession lethal weapons or pornographic material"), the genteel quasi-poverty of career military life (the commanding general of Fort Rucker's quarters were "the sort of house that a Quaker Oats assistant district sales manager in Kansas City would own"), and every lifer's fear of being riffed ("Reduction in Force. Thank you for your faithful service, and don't let the doorknob hit you . . . on your way out").

AS GOOD AS this is -- and it's good -- Griffin's at his best when the rebellion comes -- not from restive Katanga Province as Felter had anticipated, but from a disgruntled Congolese clerk turned "general," Nicholas Olenga, whose ragtag and butchering People's Liberation Army seizes a remote town and moves on Stanleyville, site of the U.S. consulate.

Felter first has to convince an incredulous LBJ of the gravity of the situation ("He was a goddamned clerk? . . . How long will it take your Colonel Mobutu to get over there and throw {him} in jail?"), but then the wheels turn in graphic, fast-paced fashion. Felter cobbles together a force of Congolese, mercenaries, Green Berets and Belgian paratroopers in an effort to recapture Stanleyville -- the rebel capital of Olenga's People's Republic of the Congo -- and liberate the European and American hostages there whom the rebels have threatened to kill, while unmarked Soviet aircraft ferry arms into Uganda for possible resupply of Olenga. This is all top-drawer.

The one place where Griffin stumbles is injecting a wildly improbable love affair between the commanding general's daughter and a recently drafted private, although Dad's so "Family Ties" laid-back about the whole thing ("Do you think going out with a private is such a good idea, honey?"), you get the feeling that a double date with Mark Rudd and Bernardine Dohrn would evince little more than a Charlie Brown frown.

This lapse from fiction to fantasy aside, just about everything else in The New Breed clicks. As the mission winds down, a Green Beret predicts of their return stateside: "Well, I don't suppose there will be flags flying and bands playing." He's got that right. Nasty little secret. Dirty little war. First-rate book.

Rory Quirk, a Washington attorney, received military training at the U.S. Army Ranger School and the British Jungle Warfare School.