The well-worn argument that the British and Commonwealth Armies’ early setbacks in the Second World War were the consequence of weaknesses in materiel and manpower (the ‘guilty men’ narrative) has been so conclusively undermined by a number of recent studies that it leaves the historian with a set of complex problems. Britain and her allies were in a sufficiently strong position materially, economically and doctrinally to prevent the disasters that overtook the Empire between 1940 and 1942. The great German offensive in the West, no less than the Japanese ‘driving charge’ in the East, was ‘a one-shot affair’, an enormous gamble. Hitler, as much as his generals, could not believe the scale and speed of their success. They had no scheme for what to do next, plans for the invasion of Britain only being confirmed in July 1940 when peace overtures were abruptly rejected.