Should America Have Bombed Hiroshima?

A panoramic view of Hiroshima after the bomb.

(LIBRARY OF CONGRESS LC-USZ62-134192)

Sixty years ago today, the bloodiest war in history came to an end as representatives of Imperial Japan signed articles of surrender aboard the battleship USS Missouri. The ceremony took place less than three weeks after Japanese Emperor Hirohito informed his people by radio that they “must bear the unbearable” and accept defeat after atom bombs had obliterated two of their major cities. Tens of thousands had been killed instantly, and the toll climbed to as many as 210,000 by the end of 1945 from residual blast and radiation deaths.

Amid all the controversy surrounding this first use of nuclear weapons, one fact remains largely unknown to Americans. It is that President Harry S. Truman and his senior military and civilian advisors believed that the planned series of land invasions of Japan this bombing prevented would result in bloody fighting that could well extend into 1947. Without the atomic bombs, the sixtieth anniversary of the end of World War II, as they saw it, might still be years away.

When the war came to its sudden and unexpected end, in 1945, the U.S. First Army and Eighth Air Force were already in the midst of their long journey from Europe to the Pacific to reinforce General Douglas MacArthur’s invasion armada. The First Army had already fought its way across France and into the heart of Nazi Germany, while the Eighth Air Force had pummeled the Reich from England.

The invasion of the imperial homeland, code-named Downfall, contained four major components:

First, a Connecticut-size area on the southernmost island of Kyushu would be seized by the end of 1945 for the construction of air bases and ship anchorages. Three quarters of a million (that’s a million) U.S. soldiers and Marines would be involved in that operation.

Next, a similar landing in the spring of 1946, involving over a million and a quarter assault troops, would be made within striking distance of Tokyo itself, on the island of Honshu.

Third, Tokyo would be surrounded and thus cut off from Japanese reinforcements by summer.

Finally, if the Japanese had not yet surrendered, Tokyo would be taken in brutal block-by-block fighting, while other U.S. forces battled their way across Honshu to cut Japan in half, much as General Sherman had cut through the American South during his drive to Atlanta and the Atlantic coast during the Civil War.

With luck and hard work, Truman believed, the deadly business of subjugating Japan might be done by the end of 1946, if much of the remaining country could be induced to surrender. As early as the summer of 1944, Joint Chiefs of Staff planners had cautiously estimated the cost of this endeavor to be “half a million American lives and many times that number in wounded,” because of the willingness of Japanese soldiers to stubbornly fight to the death.

A half century after the war, some historians would pick up much smaller casualty projections made for specific parts of the opening assault to “prove” that the number of dead and wounded would not have been nearly so dreadful. But the fact of the matter was that casualty numbers were already climbing to record levels as the fighting grew closer to Japan at Iwo Jima and Okinawa, and as the Navy fought off kamikaze suicide aircraft at sea.

Nearly 300,000 Japanese civilians had lost their lives—burned to death by American incendiary bombs—and 6 million had been made homeless even before the atomic bombs were dropped. A July 1945 War Department document grimly predicted: “We shall probably have to kill at least 5 to 10 million Japanese [and] this might cost us between 1.7 and 4 million casualties including 400,000 to 800,000 killed.”

Some civilian elements in the Japanese government had come to a similar conclusion and were determined to try to find a way to end the war before the U.S. invasion was launched. Unfortunately, the military was in firm control of the government, and Japanese moderates had to tread gingerly for fear of arrest or assassination. It was the hope of Truman and his senior advisors that the tremendous shock of the few nuclear weapons available would stampede the Japanese into a quick capitulation.

In the end, this is precisely what happened—but not before a coup attempt nearly blocked Emperor Hirohito’s surrender announcement. World War II ended on September 2, 1945, instead of late 1946 or even 1947. Without the atomic bombs, the sixtieth anniversary of the end of World War II would not yet have occurred.

—D. M. Giangreco and Kathryn Moore are the authors of Dear Harry …: Truman's Mailroom, 1945-1953—The Truman Administration Through Correspondence with “Everyday Americans” and Eyewitness D-Day: Firsthand Accounts from the Landings at Normandy to the Liberation of Paris.