The hypothetical six-carrier British force

The British scenario assumes that the European war has not intervened in the availability and development of the carrier force. Implacable, Ark Royal, Courageous and Glorious are proposed as its core. Indomitable and another Illustrious-class ship, possibly Formidable, would bring the main striking force to about six carriers. Indefatigable is also mentioned as a possibility, while Unicorn might supply additional air-group support. None of those choices establishes the force actually available to Britain for a Pearl Harbor attack in 1941. Six carriers recur because British, American and Japanese calculations are presented as converging on that scale for overwhelming damage against a major fleet base.