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On This Day: Atomic Bomb Dropped on Nagasaki

August 09, 2011 06:00 AM
by findingDulcinea Staff
On Aug. 9, 1945, three days after the bombing of Hiroshima, the United States dropped a second atomic bomb on the city of Nagasaki.

The Bombing of Nagasaki

The United States and Japan had been at war since 1941. By 1945, U.S. forces were closing in on the Japanese mainland and launching bombing attacks on Japanese cities.

On July 16, 1945, in the Trinity Test in New Mexico, the U.S. successfully detonated the world’s first atomic bomb. Maj. Gen. Leslie Groves, leader of the Manhattan Project, wrote to the secretary of war that the U.S. “now had the means to insure [the war’s] speedy conclusion and save thousands of American lives.”

Nine days later, on July 25, President Harry S. Truman and fellow Allied leaders, Josef Stalin and Clement Attlee, issued the Potsdam Declaration, an ultimatum for Japan to surrender unconditionally or face “prompt and utter destruction.”

When Japan refused to accept the terms on July 29, Truman authorized the use of the atomic bomb. On Aug. 6, the U.S. dropped an atomic bomb on the city of Hiroshima, destroying over 60 percent of the developed city and killing between 70,000 and 80,000.

The White House put out a press release 16 hours after the blast. In it, Truman demanded that the Japanese leaders accept the terms of the Potsdam Declaration. “If they do not now accept our terms they may expect a rain of ruin from the air, the like of which has never been seen on this earth,” he said.

The U.S. also dropped leaflets on Japanese cities warning civilians to evacuate. “Act at once or we shall resolutely employ this bomb and all our other superior weapons to promptly and forcefully end the war,” one leaflet stated.

Japan did not immediately accept surrender. The U.S. targeted two cities on the southern island of Kyushu for a second bombing: Kokura and Nagasaki. The bomb used would by the “Fat Man,” a shorter, wider and more complicated bomb than the “Little Boy” used on Hiroshima.

On the Pacific island of Tinian, Fat Man was loaded into the B-29 Superfortress “Bockscar” piloted by Maj. Charles W. Sweeney. The plane took off in the early morning hours of Aug. 9, headed toward the primary target of Kokura.

Poor visibility caused problems for Sweeney, who was unable to locate a plane carrying scientific observers and photography equipment that was supposed to follow Bockscar. Sweeney arrived over Kokura behind schedule and found that 70 percent of the city was cover with clouds. The plane made three runs over the city, but the crew was unable to spot a target.

With fuel running low, Sweeney and Lt. Cmdr. Frederick L. Ashworth, the plane’s weaponeer, decided to attempt the drop over its secondary target, Nagasaki. There they found the cloud cover was even worse. Sweeney and Ashworth considered dropping the bomb based on radar, against the orders they had received to return to base with the bomb if they could not see the target.

Lt. Frederick J. Olivi described what happened next: “[Capt. James] Van Pelt, the navigator, was checking by radar to make sure we had the right city, and it looked like we would be dropping the bomb automatically by radar. At the last few seconds of the bomb run, [Capt. Kermit K.] Beahan yelled into his mike, ‘I’ve got a hole! I can see it! I can see the target!’ Apparently, he had spotted an opening in the clouds only 20 seconds before releasing the bomb.”

Beahan, the bombardier, released Fat Man at 11:02 a.m. at an altitude of 1,650 feet. Though the bomb created a blast equivalent of an estimated 21 kilotons—eight more than Little Boy—the city of Nagasaki suffered less death and destruction than Hiroshima.

“The hills of Nagasaki, its geographic layout, and the bomb's detonation over an industrial area all helped shield portions of the city from the weapon's blast, heat, and radiation effects,” explains GlobalSecurity.org.

An estimated 40,000 people were killed that day, and the death toll may have climbed to over 70,000 by the end of the year.

The End of the War

Earlier in the day, the Soviet Union declared war on Japan. “The great bomb, which harnesses the power of the universe to destroy the enemy by concussion, blast and fire, was dropped on the second enemy city about seven hours after the Japanese had received a political ‘roundhouse punch’ in the form of a declaration of war by the Soviet Union,” reported The New York Times.

Japanese leaders had no choice but to surrender. “I cannot bear to see my innocent people suffer any longer,” declared Emperor Hirohito before the Japanese Supreme Council. “Ending the war is the only way to restore world peace and to relieve the nation from the terrible distress with which it is burdened.”

Japan accepted the Potsdam terms and unconditionally surrendered to the United States on Aug. 14, a day known as Victory in Japan, or V-J, Day. It marked the end of World War II.

Historical Context: World War II

Japan had allied itself with Nazi Germany and Italy to form the Axis Powers. On Dec. 7, 1941, it bombed a U.S. military base at Pearl Harbor, drawing the U.S. into World War II.

For four years, the U.S. and Japan waged war in the Pacific. By 1945, Japan had begun suffering heavy losses. It lost battles on home islands of Iwo Jima and Okinawa, and American B-29s dropped incendiary bombs on Tokyo, Nagoya, Osaka and Kobe, ravaging the cities.

Were The Atomic Bombs Justified?

Reactions to Truman's decision to use the atomic bomb are split. Many consider the bombing cruel and inhumane while others argue that the U.S. government was left with no alternative to end the war.

A feature in The Atlantic analyzes both sides of the story. It highlights Karl T. Compton’s “If the Atomic Bomb Had Not Been Used,” in which he notes “the nuclear explosions killed far fewer people than the firebombings.

Moreover, without the nuclear attacks, the Japanese would not have surrendered, even though they were militarily beaten: ‘I cannot believe,’ he wrote, ‘that, without the atomic bomb, the surrender would have come without a great deal more of costly struggle and bloodshed.’”

Thomas Powers offers a contrasting perspective in “Was It Right?” asking "how could the killing of 100,000 civilians in a day for political purposes ever be considered anything but a crime?" He does admit, however, that "the bombing was cruel … but it ended a greater, longer cruelty.”

Reference: Atomic Bomb Primary Documents

George Washington University’s National Security Archive has an extensive selection of primary resources on the atomic bomb and the end of World War II. Documents range from letters between politicians debating first use alternatives to the earliest intercepted Japanese surrender memorandums.

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