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)