1937-1941 → Japan → built up large empire in Asia + Pacific.

Even after US victory → In battle of midway → US + allies → faced potentially lengthy + costly campaign against Japanese forces → which had dug themselves into island strongholds.

Allies → came up with strategy → Island Hopping.

  • involved using air attacks + submarines → isolate Japanese-held areas → rather than try to capture them
  • Allies would then conquer the islands → which were poorly defended.
    • then use them to further cut off ships → that supplied well defended islands.
  • Idea → was to cut off some areas from their supplies of food, ammunition, and other essentials.

This approach → proved to be successful.

  • allowed allies → incur fewer casualties
  • come within striking distance of Japan itself → in just a few years.

(if allies had tried to conquer every Japanese stronghold → it would have taken much longer)