Robin Prior, who turned eighty in 2022, was for many years a senior academic at the Australian Defence Force Academy. Now a visiting professorial fellow at the University of Adelaide, he has spent a distinguished career writing about 20th-century British and imperial military history. His 2009 book on the Gallipoli campaign is regarded as one of the most incisive accounts of this confrontation, the historiography of which is notoriously fractious. His more recent work on the British experience of 1940 is rightly acclaimed. Prior is a historian who has always had trenchant views. His new book, his most ambitious yet, is a welcome distillation of a lifetime of scholarship. It is sure to inform, entertain and – no doubt as the author intended – occasionally provoke and annoy.

A word of caution is in order. The book’s subheading is misleading. If Britain’s two world wars were about anything, they were about the mass mobilisation of the nation’s industrial, financial and human resources. But there is little here about the political economy of global conflict in a machine age. Nor is there much about the experience of war at the ‘sharp edge’ – you will find no mud, blood and poetry anecdotes from the trenches in these pages. This is war as seen from the perspective of Whitehall, or at least GHQ. Its cast is composed of admirals, air chief marshals, generals and (especially) politicians. It is the relationship between statesmen who made grand strategy and the senior hierarchy of soldiers, sailors and airmen who carried it out that clearly interests Prior. Whether one regards this as a narrowly restrictive or a refreshingly focused way of thinking about military history is a matter of taste. Prior has mastered his brief as he has identified it. He offers an interpretation of events that is lucidly and judiciously argued in great detail.

A more accurate subheading might have been ‘Prime Ministers at War’, because situated at this book’s heart are the characters and judgements of the four men who led Britain from 1914 to 1918 and from 1939 to 1945. Prior’s pen is wielded scrupulously, often censoriously. His chiding is