Penguin £25 pp816

Niall Ferguson’s big new book takes its title from the most famous of all science-fiction stories. “On the eve of the 20th century,” he writes, “HG Wells had imagined a ‘War of the Worlds’ — a Martian invasion that devastated the earth. In the hundred years that followed, men proved that it was quite possible to wreak comparable havoc without the need for alien intervention. All they had to do was to identify this or that group of their fellow men as the aliens, and then kill them.”

In this panoramic study of the principal conflicts of the 20th century, centred on the second world war, Ferguson argues that economic instability, overlaid upon imperial ambitions and ethnic tensions, provoked most of the great killings. The pursuit of racial or political homogeneity has provoked countless massacres from Smyrna to Srebrenica.

Hitler’s slaughter of the Jews remains by far the most notorious, yet Stalin and Mao Tse-tung rivalled him. Japanese rejection of western hegemony in Asia seemed justified. Yet they quickly forfeited sympathy by their savagery towards the Asian societies they conquered. Ferguson, who writes with tremendous narrative verve, has in some respects assumed the mantle of Correlli Barnett, a generation on. He loves controversy, even perversity — the grenade lobbed into the cosy tea party of received wisdom. In his earlier book, The Pity of War, he attributed to the British government principal responsibility for the catastrophe that broke in 1914.

Here, he suggests that it is mistaken to perceive the second world war as beginning in 1939; rather, it started when Japan invaded China in 1937, or even when Mussolini went into Abyssinia in 1935, or when the Italians and Germans assisted Franco to overthrow the Republican government of Spain. “Appeasement did not lead to war. It was war that led to appeasement.”

He believes that the western democracies should have gone to war with the Nazis in 1938, when Germany’s military position was relatively weaker vis-à-vis France and Britain. This may be true, by a mere count of tanks and fighters. It seems much more debatable, however, whether Britain and the Dominions were psychologically ready to accept the necessity of confronting Germany in arms, as they were a year later. He remarks that America, for all its fine words in the 1930s, was at least as guilty of appeasing the dictators as were the Europeans. His indictment of the democracies is as outspoken as any by a modern historian: “The war that broke out . . . between Germany, France and Britain was as much the fault of the western powers, and indeed of Poland, as of Hitler.” The only credible British policy in the 1930s, he says, would have been to seek an alliance with Stalin against the Nazis. It is possible to acknowledge the logic of such a course, while understanding why it would have been repugnant, as well as probably unattainable, for a British government.

He is good at drollery. Noting the manner in which the public-school ethic pervaded the British war effort, he writes: “This strange combination of upper-class puerility and working-class bloody-mindedness was itself part of the secret of ultimate British success. Since they had no very lofty notions of what they were fighting for . . . the British proved difficult to demoralise.”

He contrasts the grandiose vision of the Nazis, set to Wagner, with the infinitely more homely ideal of the British, reflected in JRR Tolkien’s The Lord of the Rings. Whether or or not Tolkien acknowledged the symbolism, Ferguson says, Mordor represented the Nazi world, “a blasted industrial hell”, while the British thought of themselves as hobbits of The Shire, “plucky little underdogs pitted against an all-knowing, all-powerful foe”.

He catalogues big Axis mistakes. Britain’s doomed campaigns in Greece and Crete caused Hitler’s invasion of Russia to be delayed by two months, a period that might have been decisive in enabling the Wehrmacht to break the Red Army before winter saved Stalin. If Hitler had instead devoted 1941 to defeating the British in the Mediterranean, he could probably have succeeded. If he had committed more resources to the U-boat war, he might have won the battle of the Atlantic. If he had heeded the advice of his military commanders, he might have prevailed in Russia. The Japanese should have deployed in the Pacific some of the forces they maintained in China and Manchuria, and seized Ceylon to dominate the Indian Ocean.

Ferguson returns to the economics, however, to reach his own conclusion about such “counter-factuals”: the industrial might of the Allies was so great relative to that of Japan and Germany that it is unlikely any short-term Axis success could have altered the outcome.

The “war of the world” ended, says Ferguson, in July 1953, when the Korean war petered out. Thereafter, new economic stability and a huge rise in prosperity combined with the strategic stability of the cold war to bring an end to the great slaughters. Many of the ethnic minorities whose predicaments had helped provoke conflict had been destroyed or transferred. President Kennedy said of Germany’s partition: “A wall is a hell of a lot better than a war.”

Yet Ferguson’s concluding chapters suggest that a new era of economic instability driven by China’s rise, together with the dramatic population changes created by mass migration, the decline of western birth rates and the rise of Muslim ones, pose new dangers. “We will avoid another century of conflict,” he writes, “only if we understand the forces that caused the last one — the dark forces that conjure up ethnic conflict and imperial rivalry out of economic crisis, and in doing so negate our common humanity.”

This huge book accompanies a Channel 4 series. Ferguson’s central thesis could be more clearly argued if he did not interweave analysis of the forces that created the 20th century’s wars with narrative and comment on military events. A yearning to include everything one has discovered about a given subject is a bear trap for historians. I also doubt whether Ferguson makes his case that the forces that caused some nations to behave so appallingly in the 20th century were historically unique. We know that unprecedented numbers died in a world that contained more people and more terrible weapons. However, it seems more questionable whether the Nazis, the Japanese, the Soviets — even the Americans and British, in our least admirable moments — behaved worse than, for instance, Europeans in the 14th century, or other peoples at various moments. The Bulgarian atrocities that so distressed Gladstone and the white massacres of Native Americans took place in the 19th century. These were certainly lesser in scale, but it is hard to see how they were different. Man frequently behaves with unspeakable savagery, above all to peoples of alien races. In the 20th century, he merely became more proficient at doing so.

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