Hiroshima+and+Nagasaki

=Hiroshima and Nagasaki=

By David Mills

Introduction
In August 1945 the cities of Hiroshima and Nagasaki were completely destroyed in history's only atomic attacks. These bombings decisively ended the war against Japan, and thus brought the Second World War to a close. Presumably, this saved many American lives by staving off an invasion of the Japanese mainland, but debate persists over President Truman's motives. Did he mean only to stun the Japanese, or was he more keen to demonstrate American power to Stalin and the increasingly troublesome Soviet Union?

The Bomb
The American effort to develop an atomic bomb was called the Manhattan Project. Although it formally began in December 1942 (when President Roosevelt signed away the necessary funds), research and development for the Project began significantly earlier. Robert Oppenheimer headed research, first at the University of Chicago and later at a federal facility in Los Alamos, New Mexico. Between 1942 and 1945, Oppenheimer's team of scientists at Los Alamos developed two types of weapon, based on uranium and plutonium. Both relied on the explosive release of nuclear energy following the fission (splitting) of heavy atoms, but each had its own mechanism for starting such a reaction.

On 16 July 1945, the crew at Los Alamos successfully tested a plutonium weapon, with a yield of approximately 20 kilotons of TNT (DOE 8). It was the largest man-made explosion to date. Harry Truman, who was busy at Potsdam at the time, received the news almost immediately. He was tremendously relieved and began to bargain more forcefully with Stalin -- who already knew of the atom bomb (thanks to Russian spies in the Manhattan Project).

The Bombing
The decision to drop the atomic bomb came on 25 July 1945. Hiroshima and Nagasaki were two of four primary targets in line for nuclear destruction (Kokura and Niigata were the other two). These targets were not laid out in chronological order -- rather, bomber crews were instructed to attack wherever weather conditions were most favorable. Strikes were to begin as soon as possible after 3 August. On 29 July, Japan rejected a call for unconditional surrender from the Big Three, and on 6 August, a single B-29 dropped a uranium weapon ("Little Boy") on Hiroshima.

The effects of the detonation were horrific. Those nearest to the epicenter of the blast were vaporized. Others succumbed to burns, either from the blast itself or from the firestorm that followed. Still more fell to the radiation sickness. By the end of the year, approximately 100,000 people had died because of the blast (DOE 6).

Tokyo itself did not fully realize what had become of Hiroshima until America issued a statement on the bombing, sixteen hours after the fact. On 9 August, the Air Force delivered a flurry of pamphlets in Japan that read:

"We are in possession of the most destructive explosive ever devised by man. A single one of our newly developed atomic bombs is actually the equivalent in explosive power to what 2,000 of our giant B-29s can carry on a single mission. This awful fact is one for you to ponder and we solemnly assure you it is grimly accurate. We have just begun to to use this weapon against your homeland. If you still have any doubt, make inquiry as to what happened to Hiroshima when just one atomic bomb fell on that city" (DOE 7).

On 9 August another B-29 carried out another atomic attack, this time on the city of Nagasaki. This strike was not as deadly as the strike on Hiroshima (due to varied topography and sketchy weather conditions) but all the same it inflicted tremendous damage and loss of life.

The Aftermath
Japan surrendered the next day, under the authority of Emperor Hirohito -- who was ultimately allowed to remain as Japan's head of state. Truman had averted an all-out assault on the Japanese mainland (where two million troops remained) and tipped the postwar balance of power in one stroke. He had also ushered in the nuclear age. By 1949, the Soviet Union had nuclear bombs of its own. From there followed the development of fusion weapons and new methods of delivery, propelling the nuclear arms race to the very forefront of global politics.