AN AMERICAN ARRIVING in South Africa is immediately and repeatedly told by his hosts the one thing that he would discover alone. For all of their obvious similarities, racial and otherwise, the United States and South Africa are two very different societies, shaped by historical experiences separate and unequal. George M. Fredrickson has written a valuable and in places brilliant book that does much to tell us how those differences developed, why they are important and ultimately why one's South African hosts should take neither comfort nor refuge in those differences.

Historical siblings, America and South Africa are also histroical alternatives, different roads taken by European settler societies expanding into new continents where they both need the ideology of white supremacy to explain and justify their conquests. Fredrickson has made the centuries-long shaping of Jim Crow and of apartheid the subject of this innovative comparative study, which deftly picks apart the tangled threads of two brands of white power and traces them back to their sources.

South Africa is an America that was unable to kill off the indigenous peoples the white settlers confronted, an America in which slavery played no great economic role and quickly vanished, an America in which industrializtion did not begin until after World War II. As a result, South Africa has had to defer dealing with its "native problem" until late in the 20th century at a time when the world's standards have dramatically -- and in the South African viewpoint unfairly -- changed on that score, trapping South Africa's white nation in a time warp.

Fredrickson, professor of American history at Northwestern University, skillfully cuts back an forth between the experiences of the two countries as he stresses the continuous and mutable interaction of economic exploitation, demographic pressures, cumulative national character, sexual anxieties and other factors that forged in each nation a psychology of white domination and black degradation that would serve "to bind together the white population, or some segment of it, to create a sense of community or solidarity that could become a way of life." Slavery was tried in America and South Africa not only for apparent economic advantages but also because it seemed to hold out "the promise of a more stable and cohesive social order" among white settler that colonial authorities found increasingly difficult to control.

The Dutch burghers who waded ashore at the southern tip of Africa in the mid-17th century at about the same time that English settlers were heading for America certainly did have a different way of life in mind. The English were driven by perceptions of overcrowding at home and the national experience of already having fought a war of colonization in subduing Celtic Ireland a century ealier. They were once again intent on recreating self-sufficient communities that would of necessity displace the indigenous tribes.

The Dutch hoped to establish nothing more at the Cape of Good Hope than a trading station that would replenish ships with produce and goods obtained from the indigenous African tribes of the area. "Overriding all other considerations, including those of religion, was the economic interest of a large capitalistic enterprise" that wanted its representatives to get along with the Africans and to be nothing more than middlemen in world trade, Fredrickson observes.

The Boers turned out not to be good Company men, however, and were soon pushing off into the vast, parched interior where they collided with, defeated and ultimately co-opted African tribes into providing the quantities of labor the whites needed to run the large farms they established. The country remained an economic backwater, and the white population pressure that was driving the American Indians back from the coast did not develop in South Africa. Moreover, the Xhosa tribes showed a population vitality not apparent in the case of the Indians.

Thus, the importation of slaves was never an important institution in South Africa. There, the "quest for absolute racial dominance was destined to be less a struggle for the preservation of slavery" and the ideology that sustained it, as it was in the American South, and more an effort to maintain "proper relations between Masters and Servants." Played out under the name of apartheid, that quest continues to this day to center on master and servant relations rather than race relations as Americans understand that term.

If you look at the two historical cases over the long sweep of 300 years, as Fredrickson has and as South Africans prefer to, the American record is far worse, with its nearly final solution of slaughter and absolute dispossession of the Indians and the human plundering of institutional slavery. But South Africans will also have to register Fredrickson's conclusions that for all its imperfections and fitful halts, the United States has since the Civil War worked hard at eliminating the legalized, "dominative racism" while a new central government in South Africa has moved in exactly the opposite direction, with disastrous results.

This volume is a stunning success in accomplishing what it sets out to accomplish. It could have perhaps been even bolder in investigating the effect of political leadership on white supremacy, the one area that it shortchanges. And it would have benefited from reference tables and graphs that would enable readers to locate and compare easily population levels, economic data and geographic bases for each nation at different points in their histories. But such shortcomings in themselves indicate the richness of this volume, from which a half-dozen important works could easily be spun.