Perfect communications would not erase Japan's resource deficit

How would secure, instantaneous FTL communications change Japan's position in the Second World War?

They would improve coordination and deny the Allies many intercept opportunities, but they would prolong rather than reverse a war decided by overwhelming resource and industrial disparities.

The counterfactual grants Japan communications that opponents cannot interrupt or intercept. That would improve the coordination of dispersed forces and remove a major source of Allied intelligence. It would not create additional fuel, ships, aircraft, trained personnel, or replacement capacity. The result would be a more difficult and possibly longer war of attrition rather than a decisive Japanese victory. Command efficiency cannot replace the material capacity needed to sustain a large industrial war.