Was the use of atomic bombs (the first use of nuclear weapons in history) on the Japanese cities of Hiroshima and Nagasaki justified?
The Japanese were at that time fiercely devoted to Emperor Hirohito, who they regarded as divine. Fighting at Okinawa and elsewhere showed the Japanese forces were fanatical and would fight tenaciously to the death, and that they would choose death over dishonor. That means we can reasonably infer that the planned Allied invasion of Japan, codenamed Operation Downfall, would have resulted in horrific casualties on both Allied and Japanese sides.
Historian Victor Davis Hanson, writing in The Mercury News, argues that the attacks were strategically justified. Hanson estimated that, following the surrender of Germany, perhaps as many as 5,000 Allied bombers would have been ready to firebomb Japan, which would have been a prelude to Downfall. This operation was projected to cause a minimum of 1 million American casualties, and tens of millions of deaths and injuries among the Japanese defenders. Japanese troops had tenaciously defended the island of Okinawa with deadly ferocity, suggesting that combat on the mainland would cause a terrible waste of human life on both sides.
Other historians share Hanson’s perspective. “Truman had little choice,” wrote Antony Beevor in History Extra, “Japanese documents apparently indicate their army was prepared to accept up to 28 million civilian deaths.”
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