Why Hiroshima?

Hiroshima was chosen as the primary target since it had remained largely untouched by bombing raids, and the bomb's effects could be clearly measured. While President Truman had hoped for a purely military target, some advisers believed that bombing an urban area might break the fighting will of the Japanese people. Hiroshima was a major port and a military headquarters, and therefore a strategic target. Also, visual bombing, rather than radar, would be used so that photographs of the damage could be taken. Since Hiroshima had not been seriously harmed by bombing raids, these photographs could present a fairly clear picture of the bomb's damage.

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