US forces did not attack Japanese-held islands with no strategic importance and thus this strategy saved American lives in World War II. Since the U.S forces only attacked islands with specific strategic importance, the Americans were able to advance much quicker and as a consequence they were able to save many American lives.
The military “island-hopping” strategy was employed by the Allies in the Pacific War againsta Japan and the Axis Powers during World War II aiming to bypass heavily fortified Japanese positions and devote the limited Allied resources only on strategically important islands that lacked a well defense.