Japan's defensive perimeter created a resource-security Catch-22

Fighting across the Solomons consumed ships, personnel, fuel, and attention that Japan could not redirect to its home defenses. A tighter perimeter would have been easier to fortify and support, but withdrawal would also surrender access to the oil and other resources for which the empire had expanded. Interwar investment in hydroelectric power, coal-derived synthetic fuel, and other infrastructure might have reduced the pressure but could not remove it. Coal liquefaction available by about 1925 might have supplied a useful wartime baseline if Japan had invested early, though it could not have met the country's full needs. The limited influence of merchants and engineers in interwar leadership is offered as one reason those alternatives received too little attention. In this interpretation, Japanese leaders viewed war as the least bad option after sanctions and their own earlier expansion had closed off alternatives. Once war began, protecting the resource area spread the available force too thin to resist the American counteroffensive. Blackett Strait is one small operation within a strategic trap that geography and logistics kept tightening.