MARTIN AMIS, WHO BEGAN as a journalist with The New Statesman in the early 1970s and then moved to the writing of novels, quickly established his reputation as keen observer of contemporary social and moral decay. His analyses were never tendentious: no reflexive blaming of all woes on the usual suspects of the left-liberal imagination. On the contrary, on big canvasses like those of London Fields (1989) and Information (1995) he told insistently how his characters managed to be the authors, the petty lapsed gods, of their own petty worlds of misery, or occasionally the originators and sustainers of such happiness as they possessed. He exhibited the courage, in London Fields, of attributing decency to a fellow, Guy Clinch, who also happened to be rich; of laying bare the stupidity and nihilism that kept Keith Talent, a lowlife, on the dole; he even had the temerity to make his prime femme, Nicola Six, a bitch. Character is fate, Amis is wont to declare with the sage Heraclitus, while choristers of multiculturalism, of feminism, and of rebuke (against everything normative or traditional), simultaneously and cacophonously deny it. Amis has not withdrawn as a literary journalist and an essayist and as the biographer, of his late father, Kingsley Amis (1922-1995). While in his fiction he cultivates the comic or the satirical, in his nonfiction he tends toward the morally serious. This is the case with his new book. Koba the Dread: Laughter and the Twenty Million. The "Koba" of the title is Stalin, his revolutionary code name. The book treats of the massive blood-taint in the doctrine, Marxism-Leninism, that Stalin put murderously into effect over the twenty-five years of his reign; it is about the fact that men with revolutionary code names took over a good part of the world and dominated it in the middle, the long middle, of a century. Koba the Dread also examines the magnetic spell that Marxism-Leninism was to exert over Western intellectuals, who shouted hurrah over its imagined triumphs and who roundly, inveterately, either denied or justified its many homicidal predations.