Japan's coal wealth and oil vulnerability

Japan possessed useful domestic coal reserves and access to still more coal in Manchuria, but produced too little oil to sustain a modern industrial economy. Replacing all oil demand was impossible, while easing particular bottlenecks was a practical goal. When wartime imports contracted, military priority would force much of the shortage onto civilian transport and industry. Synthetic plants could preserve some economic output by supplying lubricants, hydrocarbon chemicals, and a limited quantity of fuel. The proposed policy aims at resilience in selected sectors rather than complete energy self-sufficiency.