Blockade lessons reshape Japanese planning

The counterfactual begins with Japan studying Germany's defeat under blockade instead of treating its own First World War experience as proof that future conflicts would be easy. A defensive reading of the war would emphasize dependence on imports and the vulnerability of a densely concentrated industrial economy. Japan would retain more coal-fired merchant shipping because it controlled coal more reliably than oil, with mechanised handling reducing the extra labour burden aboard ship. Industry would be dispersed, railways integrated, and synthetic production aimed first at lubricants and chemicals. These measures sacrifice some peacetime efficiency to keep the economy functioning when sea transport is disrupted or industrial centres are attacked.