America's blind faith in progress is the result of our geographical and historical good fortune. Meanwhile, large swaths of the Earth have seen a decline in order and development in recent decades. To wit, 20th-century Congo would shock even Tacitus or Machiavelli. The constitutional practices of ancient Rome or the deeply rooted civic culture of early-Renaissance Italy simply do not exist in much of sub-Saharan Africa today.

Michela Wrong's "In the Footsteps of Mr. Kurtz: Living on the Brink of Disaster in Mobutu's Congo " (HarperCollins, 336 pages, $26) is not a one-dimensional, moralistic tale of a terrible dictator inflicted by the Cold War West on an innocent population -- the kind of tale that apologists for Africa's failure take comfort in. Ms. Wrong, a London-based journalist who spent six years in Africa, has written a far more complex saga. She shows us a brilliant despot who used bribery to hold together a country that was never really a country and who was supported by the West for reasons at first justifiable and later not so. The result is a surgical insight into kleptocracy that challenges our assumptions of modernity.

The title is taken from a character in Joseph Conrad's "Heart of Darkness," a book that when published a century ago was intended as an attack on Western colonial behavior. Indeed, the Belgians, who persuaded scores of tribal chiefs to cede power to King Leopold in the late 19th century, offered a particularly virulent form of European colonialism. Because Belgium itself was ethnically divided between French and Flemish speakers, it had too little sense of itself to aspire to the grandeur and moral vision that, as Winston Churchill writes, the British aspired to in Sudan and elsewhere.

A Welcome Coup

When Belgium quit the Congo in 1960, elections were held and the country dissolved into violent anarchy that lasted five years. Then an army general, Joseph Desire Mobutu, staged a coup, whose stabilizing effect was welcomed by both the West and the Congolese population.

Mobutu's ability to remain in control those first few years constituted a real achievement. He was from one of the smaller of the Congo's 250 tribes, and while he had ended the secession movements, neighboring countries, just like today, were anxious for chunks of the Congo's vast and valuable land mass.

There is a tendency in the West to assume that because Third World dictators are often thugs, they are also stupid -- particularly in the case of Mobutu. But that could not be further from the truth. Mobutu, Ms. Wrong writes, "had a superb memory and on the basis of the briefest of meetings would be able, re-encountering his interlocutor many years later, to recall name, profession and tribal affiliation." Former U.S. Assistant Secretary of State for Africa Chester Crocker told the author that Mobutu "played us, and his environment, like a Stradivarius. . . . If we dared to mention IMF and World Bank concerns it [Mobutu's reply] would be: 'Do you really expect me to think that you're asking these questions of Israel and Egypt? Perhaps I should convert to Judaism?'"

Another Western official told Ms. Wrong that he never saw a photograph of Mobutu that did him justice. "'It's like taking a photograph of a jacaranda tree, you can't capture the actual impact of that color, of that tree. . . . But when you were in his presence discussing anything that was important to him, you suddenly saw this quite extraordinary personality, a kind of glowing personality. No matter what you thought of his behavior . . . you could see why he was in charge.'"

In 1990, after Western pressure forced Mobutu to democratize, he proved as adroit at manipulating the 400 political parties that emerged as he had been at manipulating a one-party state.

The 'Big Vegetables'

Mobutu stayed in power as long as he did less by thuggery than by bribery. In any society, a foreign diplomat tells Ms. Wrong, the most talented people gravitate toward the money. In Zaire, as Mobutu had renamed his country, the money was with him, so that's where the best and the brightest went. He created his own kleptocratic class of "Big Vegetables" (or grosses legumes, the jokey French idiom for bigshot), hundreds of smaller Mobutus loyal to him. Explains one expert: "Mobutu's theft . . . was a measure not of greed but of political weakness: he needed the money to remain head of one of Africa's largest, most fractious states."

It is possible that Mobutu's supposed assets of several billion dollars were in truth only $50 million, because of the rising amount of payoffs needed to forestall revolt. His extravagant lifestyle was also a significant drain: His mansion in the jungle featured French antiques and Venetian glassware. By lunch on a typical day he had already consumed pink champagne, a 1930 vintage wine and mussels flown in from Belgium.

Corruption in moderate doses can aid institution-building in early and middle phases of modernization by bringing people into the system who might otherwise stage armed revolts. But Mobutu's was a cartoon version of that principle: There were no institutions being built and, because of the state's immense mineral resources, corruption knew no limits.

Zaire was a place without any collective sensibility, where soldiers trampled on their own flag and one band of uniformed hoodlums and looters would be replaced by another. Ms. Wrong writes that in the Congo she "had made the necessary mental leap, from viewing an army as a society's shield to regarding it as a testosterone-charged time-bomb."

Mobutu used Machiavellian techniques but did not abide by Machiavellian virtue, which holds that such techniques are justifiable only in order to create a well-governed patria. He died in exile in Morocco in 1997, leaving his country in a state of anarchy no less extreme than the one in which he had found it 30 years earlier. Ironically, a new autocrat similar to the Mobutu of the 1960s may now be necessary to rescue the country from what Mobutu had inflicted in later decades.