This important work tells the compelling story of how the Royal Navy secured the strategic space from Egypt in the west to Australasia in the East through the first half of the Second World War; it explains why this contribution, made while Russia's fate remained in the balance and before American economic power took effect, was so critical. Without it the war would certainly have lasted longer and decisive victory might have proved impossible. After the protection of the Atlantic lifeline, this was surely the Royal Navy's finest achievement, the linchpin of victory. The book moves authoritatively between grand strategy, intelligence, accounts of specific operations, and technical assessment of ships and weapons. It challenges established perceptions of Royal Navy capability and will change the way we think about Britain's role and contribution in the first half of the war. The Navy of 1939 was stronger than usually suggested and British intelligence did not fail against Japan. Nor was the Royal Navy outmatched by Japan, coming very close to a British Midway off Ceylon in 1942. And it was the Admiralty, demonstrating a reckless disregard for risks, that caused the loss of Force Z in 1941. The book also lays stress on the key part played by the American relationship in Britain's Eastern naval strategy. Superbly researched and elegantly written, this seminal book adds a hugely important dimension to our understanding of the war in the East and will become required reading.