Formed and Deformed by War : US By Wayne Karlin ; (Henry Holt: $22.50; 215 pp.)

Wayne Karlin’s new novel takes us back to Vietnam-Land--not to Vietnam itself, but to that psychic geography defined for us by a school of writers who have been reading and influencing each other for a number of years now. It is sufficient for these writers, and for us, their often eager readers, simply to invoke the name Vietnam in order to conjure a mood, a sense of awfulness, weirdness, sick excitement and regret.

Even before the development of this school (whose prominent members include Tim O’Brien, Michael Herr, Robert Stone, Larry Heinemann and possibly Karlin himself), there were gifted mystifier/explicators of Southeast Asia, blenders of the exotic and the bloody. Joseph Conrad (and on another level, Somerset Maugham) said some of the same things, that Western man inevitably comes to no good in these latitudes, that he suffers humiliation no matter what he attempts. “He had flown into an idea,” as Karlin puts it, “and it had turned into heat and jungle and strange little people with an agenda of their own.” The breakdown starts as soon as the chopper touches ground, the instant the steamer noses up the brown river.

Vietnam-Land is wider than historical Vietnam. It also includes Thailand, Cambodia, parts of Indonesia, some of the Philippines and, in the novel under review, Burma (now Myanmar). Loman, the seedy hero of “US,” runs a bar in Bangkok popular with American vets, but “in the past (he had) made frequent trips to Burma. He found the country’s lack of frantic modernization restful.” But after the slaughter of democracy demonstrators on the streets of Rangoon, “Burma had joined a number of other places he preferred not to even think about anymore.”

Loman must start thinking about Burma again, thinking hard, when he finds himself leading a mission into the Burmese highlands. An American congressman hopes to dig up a few of the mythical MIAs, and Loman is coerced into service. Loman has been on other searches before. As an acquaintance tells him, “Your hobby has become a bloody industry. Films, books, organizations of earnest devotees. . . . Something didn’t come back from the war; they’re all sure it’s out there somewhere, moldering in the jungle . . . pieces of yourself you didn’t want to look at too closely.”

Along with Loman, we find ourselves enmeshed in a weird, dangerously overwrought plot, the kind that forces the author to waste a page or two every few chapters just to explain what might be going on:

“ ‘Do you know how Sadong fit in with her?’

“Weyland looked at him. ‘Sadong?’

“ ‘Khin’s daughter.’

“ ‘Aye Than,’ Weyland said. . . .

“ ‘Did Khin know?’ he pushed.

“ ‘Know what?,’ ” etc.

The point is that everyone is fooling everyone else, pretending to be something he isn’t. Loman makes a mess of things, as Western men always do (in novels), and the plot has not quite engaged us enough to justify the heavy timbering needed to figure it out.

Scenes of hideous, coolly described violence, de rigueur in Vietnam-Land novels, spice up the narrative. Karlin handles these well. Indeed, he almost always writes vividly, and his novel, while burdened by its plot and owing too much to the attitudes struck by previous writers, generously entertains as it lopes along. Nor is this a work of small ambition. It hopes to marry Western and non-Western modes of understanding in a story of contemporary realities, Burmese folklore, the history of our sorry Vietnam engagement, and one man’s wrestle with his soul. Modest it isn’t.

This may only be a warm-up for Karlin, in the way that “Typee” and “Omoo” led someone else to the white whale. In any event, we can honor him for his attempt, while especially noting his compassion for all parties to all conflicts, not excluding the young men whom we have lately made a mawkish fetish of remembering but whom he prefers to recall for us without adornment: “(Loman) stopped in the King Bar . . . and let the vets who lived in the shadows, stuck in a Twilight Zone curse of endless R&R;, buy him drinks and tell him their stories that endlessly evoked the dead and killed them again with lies until the dead, pissed off, came into the bar and sat on stools and stared, their young dead faces transparent. . . . They fondled scared bar girls and were fondled in turn, their rank, dead smell growing fouler as they got excited.”