Wartime shipbuilding widens the carrier gap

Historically, Britain shifted effort toward small escorts after war began in Europe; a fleet war with Japan would instead reward faster completion of Illustrious, Formidable, Victorious, Renown, the King George V class, and other major ships. British trade and shipyards remain largely beyond Japanese attack, allowing round-the-clock work without the disruption of bombing at home. Mobilization can also expand construction in Australia, Canada, and other parts of the empire while Britain continues buying materials from the United States. Japan faces the reverse pressure as imported fuel, rubber, and industrial materials become harder to obtain, slowing both ships and new aircraft at the moment Britain is accelerating them.