Charles McCarry tosses off a fair description of his own art halfway through his latest suspense novel, in a passage that seems to be about someone else:

"Harvey, like many successful song-writers, wrote one tune supremely well. From show to show he changed the tempo of the music and sometimes transposed whole bars, but fast or slow, backwards or forwards, his tune was always the same time. Only a trained musical ear could detect this, and he sent people whistling from theaters.'

In "The Better Angels," as in "The Miernik Dossier," "The Tears of Autumn" and "The Secret Lovers," the tune is a rather complex one built on several motifs, and though the motifs are all familiar, they are so expertly harmonized, so richly decked out with new orchestration, so artfully conducted in tempo and phrasing that their familiarity is more an asset than a liability.

Motif No. 1 is that of secrecy, an element of statecraft that has been raised to new levels of intensity in our century. Answering and balancing this is the theme of evil deeds done by good men, and complementing both of these motifs - more as a bass line than a part of the melody itself - are the harmony and tension, constantly shifting in a democratic society between those public servants who are elected (hence temporary) and those who are permanent and keep the system working.

McCarry's story is that of the 1996 presidential election in an America that has come to resemble the Weimar Republic, with our own Hitler, Franklin Mallory, confidently striding toward election. His opponent, incumbent President Bedford Forrest ("Frosty") Lockwood, looks remarkably like a combination of John Kennedy and Abraham Lincoln. Mallory (who had been president in the previous term) is ready with a program of drastic remedies for drastic problems.

The generation that grew up with Vietnam has come to power, and it seems to have done no better with the country than the generations before it. American fortunes are in decline: The Swiss franc is worth $2, crime is rampant and the polarity of rich and poor has reached the point where affluent Americans live in fortified enclaves, walled off from the chaos around them.

Mallory's solutions are strong and simple: genetic testing of all Americans for that extra chromosome that portends criminal tendencies, life imprisonment for a single small crime, concentration camps in Alaska, suspension of elections for 20 or 30 years until things settle down.

He lost the last election in the wake of revelations that he had tried to engineer the secession of part of Canada and its annexation to the United States. His opponents know that if they lose the election, they will end up in a prison camp, and Mallory has uncovered a state secret that makes their losing almost inevitable.

By the time all this has been made clear, McCarry has manipulated the reader into a curious state of mind, hoping (rather forlornly, because it looks bleak) that the good guys will steal an American presidential election from the bad guys, who appear certain to take power if the election is run honestly. The book closes on a note of hope that history may do again what it has done so often before - assimilate a mass of lies, violence and treachery and somehow make it work out positively.

This climate of moral ambiguity is familiar from McCarry's earlier novels, as it is from the books of other virtuoso composers of essentially the same melody - John LeCarre, for example, and Len Deighton in his better moments. The real moral of good fiction about espionage and suspense in our time is that right and wrong are mainly a question of allegiance, and allegiance is an arbitrary decision. If they hope to win in a struggle with the bad guys, the good guys have to become at least equally bad.

The unusual element this time is that the good guys and the bad guys are almost all Americans, the struggle takes place mostly in the United States - in government offices and Georgetown drawing rooms - and the cast of elected officials, career civil servants and media types has a distinctively Ivy League flavor, in contrast to the rather louche characters who usually populate foreign land-scapes in this sort of novel.

McCarry has found new resources for variation in his familiar melody, and fans who can recognize the beloved basic tune should be willing to welcome the new orchestration.