Iwo Jima was the island considered as a stepping stone to the jap mainland.
Iwo Jima - although not strictly a stepping stone it gave the US an airbase that was reasonably far forward and at the same time deprived the Japanese of an airbase allowing bombing raids on mainland Japan to proceed with less interference. ;
Iwo Jima was the island considered a stepping stone for an invasion of the Japanese mainland during World War II. The battle for Iwo Jima, fought from February 19 to March 26, 1945, resulted in heavy casualties and allowed the U.S. military to establish airfields for future assaults against Japan. Its capture was a key part of the island hopping strategy that ultimately aimed for the occupation of Japan itself.
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