A 1933 plan acknowledged that a fleet rushing west could face an impossible position if Japan closed every usable Philippine port. It would then have to halt in the Marshalls or Carolines, seize bases and regroup. Subsequent planning turned that contingency into a deliberate campaign across the mandated islands. The requirement to arrive early in the Philippines was reinterpreted as arrival after the danger of being cut off had been addressed. Clearing the Marshalls and Carolines would establish the secure line of communication needed to fight farther west. This progressive movement anticipated the Central Pacific campaign of World War II.
Notable Point · 1:34:37-1:37:13
Why War Plan Orange made secure bases a condition of advancing
The revised Pacific advance treated bases in the Marshalls and Carolines as prerequisites for reaching the Philippines ready to fight.