Cross-India railways versus maritime supply

Would a 1939 war with Japan justify a new cross-India railway for troops and stores?

Possibly, but planners would first compare it with the cheaper option of shipping supplies directly to eastern Indian ports closer to Burma and China.

A cross-India railway is plausible but not automatically efficient. The central calculation is whether unloading in western India and moving supplies across the subcontinent would beat sailing them directly to ports on the eastern side. Handling costs and route length could preserve maritime transport's advantage when suitable ports remained available.