Books: The rich just get richer faster

James Harkin on the forces that shaped 100 years

Twentieth Century: A History of the World 1901 to the present by J M Roberts Allen Lane pounds 20

Terrible beauty, civilised barbarism ... the temptation to reduce a century of history to an appropriately dramatic title makes cheap pundits out of some of the best historians. What this book lacks in glamour is more than made up for by the quality of its argument.

From his picture on the back flap of Twentieth Century J M Roberts looks gratifyingly long in the tooth -a qualification of sorts - and brings to his subject a wealth of experience in popular history writing. In 900 pages he is not going to introduce any new material: his aim, he says, is "a reconsideration of facts established by others and not a work of original research". Roberts locates change as the only certainty of modern society, and its increasing pace as fundamental to any characterisation of the 20th century. Acceleration in the manipulation of nature by human beings in the last 100 years, he argues, along with the integration of almost everyone into something approaching a common culture, means that the 20th century is the first to merit the title of a truly global century.

Roberts shows up the scale of change by revisiting the state of play in1901, when the fastest ships took just under a week to cross the Atlantic, whereas "now it can be flown in three-and-a half hours by men and women born before the first man-carrying flight took place". In 1901 there were hardly any drugs available to doctors for the treatment of specific diseases, and now there are hundreds: "the advance has been the result of organised scientific effort". A quadrupling of the world's population since 1901 evidences ingenious improvements in agricultural productivity: "if the world had not been able to feed a growing population human numbers would have been smaller."

Roberts is not blind to the inequalities inherent in market prosperity, but he identifies the appropriate measure of poverty as relative rather than absolute: the global poor have improved their lot with increasing industrialisation, but the rich have got richer faster. Today roughly one half of mankind consumes about six-sevenths of the world production while the other half shares the rest: things, he says acidly, "were not quite as skewed as that in 1901".

The task of pulling his story together into a tightly knit narrative leaves Roberts little room for sentimental reflection. The assassination of American President McKinley in 1901 is distinguished from that of his successor John Kennedy in 1963 because the latter evidences the emergence of a worldwide television audience. On a world-historical scale John Major's tenure as Prime Minister passes by in an instant, signifying nothing. The rise of Hitler and Nazism looks less like a metaphysical "warning from history" than a sordid abdication of political responsibility: "Some of them," says Roberts of Weimar political elites, "began to think that Hitler might be useful in their own game."

In his search for order in history, Roberts is impatient with those who dare to rock the boat. He chides the Bolsheviks for their lack of "diplomatic manners" and sniffily refers to the "noisy campaigning" of the suffragettes. Left to its own devices, he seems to conclude, the quiet motor of technical advance has succeeded where social movements have failed. Closer investigation might reveal a complex and often symbiotic relationship between the two. The Pill is held up by Roberts as an example of the progress made by medical science in the field of female reproductive health. But the Pill could hardly have found a market in the 1960s were it not for social and cultural changes surrounding the role of women in society: in turn, the increasing independence offered women by a more reliable contraceptive spurred a new generation of feminist activists to campaign on a range of social and sexual issues.

The First World War marked a slow leaking away of European hegemony, but the triumph of values bequeathed to humanity by European civilisation. Those values now properly belong to humanity as whole, but the final paradox is that they are falling increasingly out of favour on their home turf. By the middle of the 1970s, Roberts notes, doubts about interference with nature and increasing concern with the social costs of material progress were beginning to weigh heavily with many European citizens. Premonitions of tragedy, on the other hand, were sentiments that poorer countries could ill-afford: "[they] found them insignificant compared with the benefits to national income and GDP which rapid industrialisation and further technological advance might bring."

Roberts is keen to distance his own work from deterministic conceptions of history, where inexorable trends are thought to move history onwards towards irresistible conclusions. The loss of confidence which he identifies among contemporary Europeans, however, suggests that the need for qualification is all but redundant. The spectacle of tight-fisted investors groping around in search of shareholder value, together with a suspicion of innovation among anxious citizens, means that an accelerating pace of change can no longer be taken for granted in industry and is not even thought of as desirable by European electorates.

On the emerging shelf of history books written for the millennium deadline, Twentieth Century offers a robust balance-sheet in defence of the business of moving history forward. "The human race," Roberts announces, glancing up for a moment from his mass of statistics, "looks as if it is making a greater success than ever before of living on this planet."