Those fortunate enough to travel through Ian Smith's Rhodesia in the 1970s found themselves entering a time warp, with the clock put back about 30 years. Visiting Salisbury (now Harare) in those years, I was always reminded of the postwar Britain in which I grew up, a world of austerity and order, of standing to attention for "God Save the King", of listening to the wireless and watching black-and-white movies, the day punctuated by the horse-drawn milk cart in the morning and the lamplighter on his bicycle in the evening. The tiny white community of Salisbury still lived in that heroic world, suffused by a permanent glow of sepia-tone nostalgia, and proud of the nation that they believed they had constructed on their own. They perceived themselves as plucky little Rhodesia battling against the powers of evil - the "communism" threatening the African continent - rather as Winston Churchill's Britain had stood alone in 1940. They could not understand why their wonderful country had become an international pariah. To justify their obduracy, they equated the black nationalism that was spreading through Africa with the red menace that had overtaken eastern Europe, hoping this might strike a chord with the Americans. They never realised that their view was not widely shared.

To read the memoirs of Ian Smith is to re-enter that forgotten world, with all its rancour and pomposity and paranoia. Most of this very large book is an excellent read, because "good old Smithy" was an adroit politician, playing a fairly good hand and running rings around successive emissaries from Westminster and Whitehall. He makes sharp and accurate comments about some of our most revered statesmen. The late R A Butler is described (quite correctly) as "flabby, overweight, with a bloated face, his handshake like a cold fish", while the "two-faced" Lord Carrington gets a special mention for his deviousness. When Carrington resigned from Margaret Thatcher's government over his handling of the Falkland Islands crisis, Smith and his friends "drank a toast to Argentina". By contrast with Smith's treatment of Tory politicians, Harold Wilson and the various Labour bumblers who were sent out to Salisbury escape quite lightly.

Smith was a small fish in a small pond, but he had his moments of glory on the international stage, meeting prime ministers and presidents, and he wrote everything down. He remembers everything and forgives no one, and he retells his story, in Churchillian tones, as an epic of appeasement and betrayal. He condemns the British for appeasing Africa's black nationalists, and he blames the South Africans for their treachery. Had he lived 30 years earlier, his views would have been commonplace; he was wholly at home with the Britain of Lord Salisbury, Julian Amery and Douglas Bader, and he would probably still enjoy a drink with Norman Tebbit. His finest hour, one that he never forgot, was fighting with the RAF in the Second World War. (In spite of his later, strident anti-communism, typical of the whites in Africa, he was actually rescued and looked after by the communist partisans in Italy.)

The Rhodesian generation that returned to Africa from the war fully expected that their country would soon be granted independence, like the other dominions in the empire. In those days, there was no nonsense about "majority rule". But the political leaders of the time had eyes larger than their stomachs, and delayed matters, believing that they could profitably join forces with some of their neighbours. Sir Godfrey Huggins, later Lord Malvern, wanted to unite the agricultural wealth of Southern Rhodesia with the copperbelt of Northern Rhodesia (which became Zambia), while his successor, Sir Roy Welensky, had visions of joining up with the mineral-rich Congolese province of Katanga. What a Central African powerhouse that might have been!

The foolishness of such notions soon came up against the reality of a large African population that had no wish to be run by a tiny group of white settlers. The Southern Rhodesian whites had no choice but to go it alone, as minor allies of the far more racist white republic of South Africa, with which they rarely saw eye to eye. Indeed, much of this book details Smith's disagreements with his closest ally, the South African prime minister John Vorster, who eventually betrayed him at Henry Kissinger's bidding.

This book appeared in an earlier version in 1997, but with the current interest in Zimbabwe, aroused by the activities of Robert Mugabe, Smith cannot resist writing "I told you so", in clever schoolboy fashion. The final hundred pages include his gloss on the Mugabe years, views that are reiterated almost every day in the British press.

Why do we all seem to have such a disproportionate hatred for Mugabe? After 20 years of his rule, Zimbabwe is, by all accounts, in a pretty sorry state. Yet so is much of the rest of Africa. Who can guarantee that Mugabe's successor will prove any more successful? The heir to a miserable colonial legacy, the victim of cold-war quarrels, the unfortunate beneficiary of the attentions of the IMF and the World Bank, with the ever present horrors of war and famine thrown in, Africa has presented a sad picture over the past half-century. The French agronomist Rene Dumont, who died last month, wrote his ground-breaking book L'Afrique noire est mal partie almost 40 years ago; things have got considerably worse since then. So why is Mugabe's Zimbabwe singled out for such fierce criticism in the British (if not in the French) press?

No doubt Mugabe also lives in a time warp, imagining that the glory days of the old third world are still with us. Time was when a far-reaching land reform - expropriating the acres that the white settlers had stolen from black people at the point of the bayonet within the previous century - would have been widely welcomed, at least on the left. In the 21st century, such revolutionary enthusiasm seems out of place. Handing over white land to blacks is portrayed as the height of economic folly. Who wants to turn Zimbabwe into Haiti?

Part of the problem in Zimbabwe (and, by extension, in South Africa) is that liberal whites in Africa - of whom Peter Hain is the perfect personification - have little understanding of the extent to which they are disliked by the vast African underclass. The novelist Anthony Trollope, writing in his book South Africa, published in 1878, had a much clearer vision of the problem: "The condition of the Kaffir has been infinitely improved by the coming of the white man; but were it to be put to the vote tomorrow among the Kaffirs whether the white man should be driven into the sea, or retained in the country, the entire race would vote for the white man's extermination."

Zimbabwe, like South Africa, has been furnished with the veneer of the white man's civilisation, well described by David Blair, the Daily Telegraph correspondent forced to leave Harare last month. He noted how prosperous the country seemed only three years ago, with its "office blocks, glittering shopping malls and multiscreen cinemas". Compared with "the potholed shambles" of Yoweri Museveni's Kampala (usually well regarded in the west), Harare's "supermarkets sold everything, cinemas showed the latest films and you could drive to spacious houses in leafy suburbs along immaculate roads with . . . functioning traffic lights". God was in his heaven, and that was just the other day, in 1999. Today, as the Telegraph headline proclaimed above Blair's article on 28 June, "Mugabe's lust for power has thrown the country I knew into a vortex of violence".

Well, perhaps we should start to recognise that this is a picture of the real Africa beneath the veneer. "It is the far future of Africa . . . which depresses me," wrote Olive Schreiner in 1883, in The Story of an African Farm. She was more radical an interpreter of African realities than Trollope, and she put her finger on a truth that has not gone away. "I believe we are standing on the top of a long downward slope. We shall reach the bottom at last, probably amid the horrors of a war with our Native races, then not the poor savage or the generous race we might have bound to ourselves by a little generosity or sympathy, but a fierce, half-educated, much brutalised race, who will have their own!"

Schreiner saw that day coming "50 or 60 years hence". Her foresight was admirable; her timing was out by only half a century.

Richard Gott is working on a book about imperial rebellion