The reason why Japan strongly defended Iwo Jima was because It was considered part of the Japanese homeland.
The Island of Iwo Jima was quite close to the Japanese Homelands which meant it was treated as a part of the nation.
The Japanese therefore defended it heavily because they did not want a part of Japan to fall to the allies.
Find out more on the Iwo Jima Campaign at https://brainly.com/question/17164811.
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