General Situation in the Spring of 1942
Before the outbreak of war the Chiefs of Staff had forecast that the United Kingdom would require a period of two years of defensive war in order to build up sufficient armed strength for a counter-offensive.
By the Spring of 1942 not only had that difficult defensive phase been surmounted, but the situation was far more favourable than the Chiefs of Staff had anticipated. Active intervention by the United States, which had appeared “doubtful” in 1939, had been provoked by the bombing of the American naval base at Pearl Harbour by Japan on the 7th December, 1941; and within a few weeks the vanguard of the American armies was arriving in this country. The intervention of Russia, too, regarded as hopeful in 1939, had succeeded beyond expectations. The supreme German effort to capture Moscow in 1941 had been checked; and it seemed inevitable that the German Command would have to resume the Eastern offensive in 1942 in order to obtain essential oil from the Caucasus, and to break the Russian army, before taking on further commitments.
The Anglo-American policy in face of this situation, discussed at Washington in February, 1942, was to send war material to Russia as a first priority, and also to take offensive action by sea, air and land as major diversions. The United Kingdom was to be administered and planned as a base for the accommodation and supply of British and American forces destined for offensive operations on the Continent (Operation Round-up). Three British Armies were being assembled: the First in Scotland, the Second in the Midlands, and a Canadian Army in South-East England; the South-Western counties and Northern Ireland were allotted for the assembly and training of American troops.