Midway's fleet-building lesson: make the force viable

Adding carriers or Kongos only helps if the accompanying cruisers, destroyers, and organization make the enlarged formation defensible. A force sent into combat needs to be viable, capable, and sufficient for its mission. Half measures needlessly risk its crews. A balanced fleet needs adequate strength at the chosen point and must be organized so commanders can use it when required. The closing problem asks how Japan in 1937 might have expanded escort forces without interrupting Yamato, Musashi, and other major projects. One option was to extend the existing policy of subsidizing merchant ships designed for rapid wartime conversion into carriers or other auxiliaries, but Japan's industrial and strategic constraints allowed no easy solution.