This Day In History: 08/06/1945 - Atomic Bomb Hits Hiroshima

This Day In History: 08/06/1945 - Atomic Bomb Hits Hiroshima

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President Harry Truman orders the Enola Gay to drop the atom bomb on Hiroshima, Cy Young joined major league baseball, the first woman swims the English Channel, and Jamaican independence is declared in This Day in History video. The date is August 6th. The atom bomb was also dropped on Nagasaki which helped end World War II when Japan surrendered.

For one reporter, 1945 visit to Hiroshima was about more than a scoop

WASHINGTON, Aug. 6 (UPI) -- The first atomic bomb to be used as a weapon was dropped on Hiroshima, Japan, on Aug. 6, 1945, but Americans wouldn't know the extent of the devastation for another three weeks when reporters were allowed into the city to survey the scene.

A UPI article from that day says the results of the bomb were still not known, "but military men here said the bomb's potentialities stagger the imagination."

Tokyo radio reports also couldn't put any hard figures on the losses, but said the event had caused so much damage that the atomic bomb "is sufficient to brand the enemy in the ages to come as the destroyer of mankind." Officials there initially believed the Americans had dropped multiple bombs on the city, thinking the destruction was simply too great to come from a single weapon.

Bodies were so badly burnt and beaten by the heat and collapsing structures that for days Japanese authorities couldn't even identify the gender of some victims. History would eventually show an estimated 80,000 people died immediately in the blast, a toll that -- due to injuries and radiation -- rose to about 140,000 by the end of the year.

American journalists filed their first reports from Hiroshima at the end of August, after the second atomic bomb hit Nagasaki on Aug. 7 and after Japan surrendered, ending World War II on Aug. 15. But one correspondent got there first -- Leslie Nakashima, who had purely personal reasons to visit Hiroshima on Aug. 22.

Nakashima, who worked on the copy desk at the Japan Times, filed the first personal account of the scene to appear in American newspapers.

He gave the report to a correspondent for UPI, known then as United Press. Nakashima worked for UP's Tokyo bureau until it closed after the United States entered the war in 1941.

He traveled to Hiroshima not just to get the scoop, though he wanted to make sure his mother was still alive. Nakashima, his wife and two daughters had left the city just two weeks before the atom bomb dropped. His mother stayed behind.

"As I trod my way through the debris wondering if my mother was still alive, I realized the reality that Hiroshima city had been destroyed through the stupendous destructive power of a single atomic bomb," he wrote.

Nakashima found his mother's house -- a little more than two miles from the city center -- with walls smashed in and the roof shattered. But she was safe.

She had been in a relative's vegetable field when the bomb hit just after 8 a.m. that day. She saw the flash.

"She immediately threw herself face-down on the ground. She said she heard a terrific explosion and getting up, she saw columns of white smoke rising from all parts of the city high into the sky," Nakashima wrote.

"She said she then started running to her home as fast as she could because she didn't know what was coming next. Why she suffered no burns from the ultraviolet rays of the bombs is amazing."

Earlier in his account, Nakashima described what it was like seeing the destroyed city center for the first time from the train station, which he said "had gone out of existence."

"There's not a single building standing intact in the city — until recent of 300,000 population. The death toll is expected to reach 100,000 with people continuing to die daily from burns suffered from the bomb's ultraviolet rays."

The only buildings he could see on the skyline were those of a seven-story department store, a five-story newspaper building and a two-story bank. They were mere skeletons.

"There remained no trace whatsoever of private dwellings."

Nakashima also showed some concern about how the nuclear fallout from the bomb might affect his health.

"During this interval it is likely that I inhaled uranium because I'm still troubled with a loss of appetite and the least little exertion finds me tired," he wrote.

After the end of WWII, Nakashima found himself in a delicate diplomatic situation. After the United States entered the war, he had his Japanese citizenship reinstated — which he had renounced in favor of U.S. citizenship when he was 23, a multi-part series on the Hiroshima Peace Media website said.

He attempted to regain his American citizenship after the war, but to no avail. His editors at UPI even petitioned the U.S. State Department, but Nakashima ultimately remained in Japan, writing for UPI until his retirement in 1975.

Nakashima died in 1990 at age 88, but before he did he wrote once more about his personal experience in Hiroshima in 1945. On the 40th anniversary of the bombing in 1985, he said it was hard to remember the city as it had been in the war.

"An uninformed visitor today would have no inkling of the destruction then. Modern Hiroshima is a city of tree-lined streets and river banks, lush trees and benches where people sit enjoying summer's evening cool," he wrote.

"And there is a new railway station where I once found nothing. It is a seven-story building with a beer garden and steam bath on the roof, a 155-room hotel, restaurants, stores and even a medical clinic."

Nakashima wrote that while the "thriving, modern city" then boasted a population of more than 1 million, the citizens had not forgotten the "horror of the bombing."

"Their appeal is simple and sincere: Abolish nuclear weapons. Their slogan reflects that sentiment: 'No more Hiroshimas.'"

U.S. drops the atomic bomb on Hiroshima in 1945

WASHINGTON, D.C., Aug. 6 - The most terrible weapon in history - an atomic bomb with more explosive power than 20,000 tons of TNT - was dropped on Japan last night, it was disclosed today as President Truman hurled a new ultimatum at the [Japanese], warning them to surrender or be wiped out.

In revealing the most closely guarded secret of World War II, the President announced in a dramatic statement issued through the White House:

"Sixteen hours ago (7 P.M. Sunday, New York time) an American airplane dropped one bomb on Hiroshima, an important Japanese army base. The bomb had more power than 20,000 tons of TNT. It had more power than 2,000 times the blast power of British 'Grand Slam,' which is the largest bomb ever yet used in the history of warfare… it is an atomic bomb. It is a harnessing of the basic power of the universe. The force from which the sun draws its power has been loosed against those who brought war to the Far East."

The extent of damage from superbomb No. 1 was not immediately learned. A War Department statement said that "reconnaissance planes state that an impenetrable cloud of dust and smoke covered the target area."

"As soon as accurate details of the result of the bombing become available, they will be released by the Secretary of War," it added.

(The Associated Press pointed out that the one atomic bomb dropped on Japan carried a wallop more violent than 2,000 B-29 superfortress normally could hand a city, using the old type TNT bombs. One B-29 ordinarily can deliver about 10 tons of TNT bombs to a target.)

Last night's bomb hit Hiroshima, on the Inland Sea, on the southeast coast of the main [Japanese] home island of Honshu. Truman warned that others would strike if the [Japanese] did not surrender immediately.

"It was to spare the Japanese people from utter destruction," the President said, "that the ultimatum of July 26 was issued at Potsdam. Their leaders promptly rejected that ultimatum. 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. Behind this air attack will follow sea and land forces in which numbers and power as they have not yet seen and with the fighting skill of which they are already aware."

Even Deadlier Ones Coming.

War Secretary Stimson revealed that even deadlier atomic bombs will soon be made. "Improvements," he said, "will be forthcoming shortly which will increase by several fold the present effectiveness" of the terror weapon.

Stimson flatly declared that "we are convinced that Japan will not be in a position to use an atomic bomb in this war," and added that "it is abundantly clear that the possession of this weapon by the U.S. even in its present form, should prove tremendous aid in the shortening of the war against Japan."

The use in combat of the single atomic bomb was the culmination of three years of effort by science, industry, and the Army. So closely guarded was the secret of the new weapon that 125,000 workers at three hush-hush plants in Richland, Wash. Oak Ridge, near Knoxville, Tenn., and near Santa Fe., N.M., never knew what they were producing, in more than two and one-half years.

On the super weapon, which works on an entirely new theory, the U.S., in cooperation with the British, gambled $2,000,000,000 that scientists could smash the atom, thus releasing the deadliest source of power ever discovered. Truman said that "we have spent $2,000,000,000 on the greatest scientific gamble in history and - won."

The atomic bomb uses uranium as the essential ore in its production. War Secretary Stimson said that "steps have been taken and will continue to be taken to insure adequate supplies of this mineral."

Race of Scientific Minds.

President Truman's statement revealed that the bomb, despite its imagination-staggering deadliness, has an "exceedingly small" physical size, which confounded workers at the three atomic bomb plants. "They see great quantities of material going in and they see nothing coming out of these plants," he said, "for the physical size of the explosive charge is exceedingly small."

The history of the atomic bomb is also the history of feverish race among Germany's scientific minds, and the combined scientific minds of the U.S. and Great Britain. The Battle of the Laboratories," as President Truman called it, "held fateful risks for us as well as the battles of the air, land and sea, and we have now won the battle of the laboratories as we have won the other battles."

Prior to 1939, it was an accepted scientific belief that, theoretically, the atom could be smashed to release atomic energy. No one, however, knew any practical method of doing it. By 1942, the Germans, President Truman said, were working 24 hours a day to find a way "to add atomic energy to the other engines of war with which they hoped to enslave the world. But they failed."

"Beginning in 1940, before Pearl Harbor, scientific knowledge useful in war was pooled between the U.S. and Great Britain, and many priceless helps to our victories have come from that arrangement," he continued. "Under that general policy the research on the atomic bomb was begun. With American and British scientists working together, we entered the race of discovery against the Germans."

Experiments Conducted Here.

The late President Roosevelt and former Prime Minister Churchill, Truman said, agreed that experiments should be conducted in this country, free from bombing attack and threat of invasion.

Highly praising the resultant success of the combined Anglo-American efforts, the President commented: "What has been done is the greatest achievement of organized science in history. It was done under high pressure and without failure."

With use of the shattering new weapon, he added, "we are now prepared to obliterate more rapidly and completely every productive enterprise the Japanese have above ground in any city. We shall destroy their docks, their factories, and their communications. Let there be no mistake we shall completely destroy Japan's power to make war."

Truman said he would recommend to Congress establishment of a commission to control production and use of atomic power in the U.S., and that he would "give further consideration and make further recommendations" to Congress as to how atomic power can become a "powerful and forceful influence towards the maintenance of world peace."

Stimson announced that the man who directed the Army's $2,000,000,000 job of discovering and perfecting atom-smashing was Major Gen. Leslie R. Groves, formerly of Pasadena, Calif., who now lives here. Groves, for the past three years, has held the title of commanding officer of the "Manhattan Engineering District," the phony name given the hush-hush project to fool spies.

From the Archives, 1945: The terrible fate of Hiroshima

Photographs of Hiroshima taken after the atomic bomb raid reveal a terrible story. The area destroyed in this single volcano lies in ashes and rubble, with here and there a reinforced wall left sadly standing.

A communique issued from the headquarters of General Spaatz announces that four and one-tenth square miles, or 60 per cent., of Hiroshima, which is as large as Brisbane, was wiped out by the bomb.

The announcement is based on reconnaissance photographs, which showed additional damage outside the completely destroyed area.

Answering a question why Hiroshima, rather than Tokio, was chosen as the first target, an army spokesman replied: “Maybe we did not want to risk hitting Government buildings and destroying the people who may make the decision to surrender.”

Tokio Radio’s version of the raid said the impact was so terrific that practically all living things, human and animal, were literally seared to death. All the dead and injured were burned beyond recognition.

The 'Little Boy' atomic bomb, the type detonated over Hiroshima on Aug. 6, 1945. Credit: AP/US Department of Defence

The broadcast added that the effect of the bomb was widespread. Those out of the doors were burned to death, and those indoors were killed by indescribable pressure and heat, Houses and buildings were smashed, including emergency medical facilities.

Another broadcast warned the Japanese homeland to brace itself for new atomic bomb attacks. Osaka Radio said since it was presumed that the enemy would continue to use the new bomb the authorities would point out measures to cope with it immediately this was possible.

A special session of the Japanese Cabinet has been called to discuss “internal and foreign matters.”

The photographs show clearly that Hiroshima’s heart has been wiped out by a giant bulldozer. Only a few concrete structures believed to be air raid shelters remained standing, but even they have been burned inside. Seven river streams and several manmade firebreaks, including one three blocks wide, which were among the best seen in Japan, failed to stop the flames.

Photographs also show smoke formations absolutely new to experienced photo observers. From a base of black smoke like a rugged mountain, a graceful mushroom column of white smoke soared to 20,000 feet. At the top of the column before it billowed out into a mushroom effect air currents had seemingly decapitated it and left a smokeless space of nearly 1000 feet.

An expert said there was no comparison between a normal conflagration and a fire caused by the atomic bomb. He recalled that when Yokohama was burned it looked as though smokepots were burning throughout the city, whereas an immense smoke and dust mushroom plumed over Hiroshima.

As the atomic bomb dropped squarely on the centre of Hiroshima the Super-Fortress crew which carried it felt the concussion like a close explosion of flak although they were 10 miles from the target. Colonel Paul Tibbets, the pilot, described the explosion as tremendous and awe-inspiring. Colonel Tibbets, who was specially trained for the mission, was awarded the Distinguished Service Cross as he stepped from the plane after returning.

Ticklish Work

Captain W. Parsons, the US Navy ordinance expert, who designed the atomic bomb, said he began in June, 1943, to perfect an explosive that could be carried with comparative safety in a plane from the time required to fly from the Marianas to Japan.

“The atomic bomb cannot be controlled like other bombs,” he said. “It must be checked and patted to the last minute by the weaponeer. This will be the case until it is more fully developed.”

Details of the bombing were disclosed at a press conference attended by General Spaatz, who said the bomb was the most revolutionary development in history. General Spaatz was obviously highly elated, and added: “If I had had it in Europe it would have shortened the war by six or eight months.”

Major-General Le May said if the bombs had been available there would have been no need for D-Day in Europe.

General Spaatz announced that more Super-Fortresses from the Marianas were ready to follow with atomic bombs. He added that a leaflet campaign would inform the Japanese people that they would be atom-bombed, and could expect more in the near future.

Generals Spaatz and Le May left no doubt that they believed the air forces could beat Japan into unconditional surrender with this new and terrible weapon, which General Spaatz likened to 2000 Super-Fortresses fully loaded with incendiary and demolition bombs.

Future Targets

The US Army and Navy Air Forces have reached a generally satisfactory understanding concerning future air targets in the Japanese homeland. They will have been divided into areas. The Army will strike in one area, while the Navy hits another. Super-Fortresses will pound targets jointly selected.

The bomb dropped on Hiroshima was so small that it could have been carried by a fighter plane.

Tokio Radio claims that Hiroshima was an open city, and says authorized bombing was a violation of international law, which forbids belligerents an unlimited choice in the means of destruction.

The radio quoted the religious leader Toyohika Nagawa, who contrasted the bombing with “Japan’s careful and thoughtful air raids on Shanghai and Nanking.”

Read a Schoolboy's Eyewitness Account of Hiroshima

W hen the Japanese surrendered in World War II, the historic news was all but eclipsed by the world-altering event that led up to it: the dropping of the atomic bomb on Hiroshima, which happened 70 years ago Thursday.

“The greatest and most terrible of wars ended, this week, in the echoes of an enormous event&mdashan event so much more enormous that, relative to it, the war itself shrank to minor significance,” read TIME’s first sentence of the first story that ran the first week after. “The knowledge of victory was as charged with sorrow and doubt as with joy and gratitude. More fearful responsibilities, more crucial liabilities rested on the victors even than on the vanquished.”

It was clear to all then that a great force had been unleashed, and those who had survived the awful war would be left to try to harness it. In 1985, on the 40th anniversary of the bombing of Hiroshima and Nagasaki, TIME looked back at the legacy of the Atomic Age. As part of that special issue, Yoshitaka Kawamoto, the director of the Hiroshima Peace Memorial Museum, shared his memories of that day in 1945.

Kawamoto was a 13-year-old student at a middle school only about a half-mile from the site of the explosion. In the moment of impact, most of his classmates were instantly killed. Those left alive cried out, or sang to try to attract the attention of anyone who might help. The horror, however, had only just begun:

But then the singing and the cries grew weaker. My classmates were dying one by one. That made me very frightened. I struggled to free myself from the broken fragments, and looked around. I thought that gas tanks had exploded. Through a hole in the roof I could see clouds swirling in a cone some were black, some pink. There were fires in the middle of the clouds. I checked my body. Three upper teeth were chipped off perhaps a roof tile had hit me. My left arm was pierced by a piece of wood that stuck in my flesh like an arrow. Unable to pull it out, I tied a tourniquet around my upper arm to stanch the flow of blood. I had no other injuries, but I did not run away. We were taught that it was cowardly to desert one’s classmates. So I crawled about the rubble, calling, ‘Is there anyone alive?’

Then I saw an arm shifting under planks of wood. Ota, my friend, was moving. But I could see that his back was broken, and I had to pull him up into the clear. Ota was looking at me with his left eye. His right eyeball was hanging from his face. I think he said something, but I could not make it out. Pieces of nails were stuck on his lips. He took a student handbook from his pocket. I asked, ‘Do you want me to give this to your mother?’ Ota nodded. A moment later he died. By now the school was engulfed in flames. I started to walk away, and then looked back. Ota was staring at me with his one good eye. I can still see that eye in the dark.

Read the rest of Kawamoto’s story, here in the TIME Vault:A Fire in the Sky

World War 2: Shock reason atomic bomb creator escaped Hiroshima mission exposed

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Hiroshima: How atomic bomb creator escaped mission

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VE day is fast-approaching, with celebrations set to commence across Europe this Friday. On Tuesday May 8, 1945, the Nazi regime in Germany officially surrendered to the Allies, days after Adolf Hitler&rsquos suicide.

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Although the war was officially over in Europe, battle and conflict still raged elsewhere in the world.

In the Far East and the Pacific, World War 2 would still rage for another three months.

The redeployment of British soldiers to the other side of the world came as a stark reality check for many.

Troops, ironically, changed the acronym for the British Liberation Army (BLA) &ndash the designation for the force sent into action in north-west Europe &ndash as &ldquoBurma Looms Ahead&rdquo.

World War 2: Richard Feynman was supposed to accompany the pilots when dropping the bomb (Image: GETTY)

Atomic Bomb: Pictured is the Little Boy bomb that was dropped on Hiroshima (Image: GETTY)

Japan, then an Axis power, with its stoic determination held on the longest.

The imperial power would not surrender until September 1945.

With victory in Europe, the Allied powers wanted a fast and efficient end to the war: so came the atomic bomb.

Drawn up by a group of world-leading scientists in California known as Project Manhattan in order to reach nuclear power before the Nazis, two bombs would go on to mark the end of the war once and for all.

Trinity Tests: The atomic bomb tests were so successful that Feynman wasn't required to go to Japan (Image: GETTY)

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Among the team of scientists, Nobel Prize-winning physicist Richard Feynman was said to have been vital in ramping up the creation of the atomic bomb.

He was expected to accompany the pilots when the bomb was dropped on Hiroshima should anything go wrong.

Yet, during the BBCs 2013 documentary, The Fantastic Mr Feynman, his sister Joan Feynman revealed how he had managed to escape the nerve-racking ordeal.

She said: &ldquoHe was expected to go as the scientist with the first flight.

Project Manhattan: Feynman made huge contributions to the bomb but fell into a depression afterwards (Image: GETTY)

Some of the members of Project Manhattan discussing the atomic bomb (Image: GETTY)

&ldquoBut the bomb was so successful they decided they didn&rsquot need a scientist.

&ldquoSo he did not go otherwise he would have been in that plane.&rdquo

The bomb exploded above the Japanese city of Hiroshima on August 6, 1945, killing more than 80,000 people.

Three days later the second bomb was detonated at Nagasaki.

Nuclear war: Several countries around the world hold nuclear weapons (Image: Express Newspapers)

During the documentary, Feynman reflected on the aftermath of the bomb in the US.

He said: &ldquoThere was a very considerable elation.

&ldquoQuite a lot of parties and people got drunk.

&ldquoIt would make a tremendously interesting contrast of what was going on is Los Alamos (Project Manhattan&rsquos base) at the same time of what was going on in Hiroshima.&rdquo

VJ Day: A picture of the aftermath of Hiroshima following the dropping of the atomic bomb (Image: GETTY)


Far from celebrating, Feynman fell into a great depression.

He said: &ldquoMaybe from just the bomb itself and maybe for some other psychological reasons I had just lost my wife, I was really in a depressive condition.&rdquo

His friend and fellow physicist Freeman Dyson noted: &ldquoHe had had this great triumph on the technical level at Los Alamos.

&ldquoBut then of course, a terrible let-down afterwards.

&ldquoHaving run this tremendous race and then at the end of it concluded that it wasn&rsquot all that worthwhile.&rdquo

In 1945, atomic bomb hits Hiroshima

When President Harry S. Truman announced to the nation at 11 a.m. Aug. 7 that an immeasurably destructive atomic bomb had been dropped on Hiroshima 16 hours earlier, the allies and the people of the western world took a deep breath victory was finally in sight.

The Enola Gay, the B-29 Superfortress that dropped the bomb, launched the power of 2,000 TNT bombs on the Japanese city. The response in Greenville was primarily wonder and relief — the possibility that the men arriving home from Europe might not be sent to the Pacific and that those stationed on once-unknown islands might not be part of a mighty invasion force.

Three days later, the news that a second bomb had destroyed Nagasaki was accompanied by the president’s warning that other Japanese industrial cities would be leveled if unconditional surrender did not come soon. The destruction at Hiroshima and Nagasaki, together with the Russians advance into Manchuria, finally led to Japan’s unconditional surrender a week later.

Editor's note: For more than 140 years, The Greenville News has told the story of our community and the people who live here. Each day this year we are publishing a brief piece of our history – Greenville's story.

Discover the facts about the atomic bombing of Hiroshima, Japan during World War II

The first atomic bomb detonated over a populated area occurred on August 6, 1945 at 8:15 AM over the Japanese city of Hiroshima. The bomb name was Little Boy . The bomb type was a gun-assembly bomb. It was deployed by a B-29 bomber named the Enola Gay . It was airburst at 580 m (1,900 ft) above the city with a TNT equivalent of 15,000 tons (estimated).

Hiroshima had not been attacked during World War II before the atomic bomb was dropped.

How many people died from the atomic bombing of Hiroshima?

The population of Hiroshima in June of 1945 was 255,260. Approximately, 70,000 people or 27% of the total population were killed outright or shortly after the blast. Approximately, 140,000 people or 55% of the total population were dead by year’s end.

What are the symptoms of radiation injury?

General effects of radiation injury include confusion, convulsions, weakness, and fatigue. Other symptoms include hair loss, inflammation of the throat, central nervous system damage, internal bleeding, bleeding into the skin (petechiae), gastrointestinal symptoms, and skin reddening (erythema). Long-term effects included cataracts and cancer. Deaths and illnesses from radiation injury continued to mount through the succeeding decades.

Reconstruction of Hiroshima began in 1950, and Hiroshima is now the largest industrial city in Japan’s Shikoku and western Honshu regions. Hiroshima became a spiritual centre of the peace movement for the banning of nuclear weapons. Peace Memorial Park, at the epicentre, contains a museum and monuments dedicated to those killed by the bombing. Atomic Bomb Dome, one of the few buildings not obliterated by the blast, was designated a UNESCO World Heritage site in 1996.

The bombing of Hiroshima

On July 16, just hours after the successful completion of the Trinity test, the heavy cruiser USS Indianapolis left port at San Francisco with the gun assembly mechanism, roughly half of the U.S. supply of uranium-235, and several Los Alamos technicians. The remainder of the U.S. uranium-235 stockpile was flown to Tinian on transport planes. Upon the arrival of the Indianapolis at Tinian on July 26, assembly began on the bomb, dubbed Little Boy. The Indianapolis departed Tinian after the delivery, but it was sunk en route to the Philippines by the Japanese submarine I-58 on July 30. Hundreds of crew members who survived the torpedo attack died in the water while awaiting a rescue. The components of a second bomb, a plutonium device nicknamed Fat Man, were transported to Tinian by air. By August 2, 1945, both bombs had arrived at Tinian, and U.S. commanders were waiting only for a break in the weather to order the execution of Special Bombing Mission 13—an atomic attack on the Japanese home islands.

Groves had chaired the committee responsible for target selection, and by the end of May 1945 the list had been narrowed to Kokura, Hiroshima, Niigata, and Kyōto, all cities that had not yet been subjected to Gen. Curtis LeMay’s strategic bombing campaign. Kyōto, Japan’s ancient capital, was consistently placed at the top of the list, but Stimson appealed directly to Truman to remove it from consideration because of its cultural importance. Nagasaki was added in its place. Hiroshima became the primary target because of its military value—the city served as the headquarters of the Japanese Second Army—and because planners believed that the compactness of the urban centre would most vividly demonstrate the destructive power of the bomb.

The pilots, mechanics, and crews of the 509th Composite Group of the Twentieth Air Force had all trained with the specially modified B-29s that would serve as delivery vehicles for the bombs. Col. Paul W. Tibbets, Jr., the commander of the 509th, would pilot the B-29 that would drop the first bomb. His 11-man crew included Maj. Thomas Ferebee as bombardier and Manhattan Project ordnance expert Capt. William (“Deak”) Parsons as weaponeer. Tibbets personally selected plane number 82 for the mission, and, shortly before taking off at approximately 2:45 am on August 6, 1945, Tibbets asked a maintenance worker to paint his mother’s name—Enola Gay—on the nose of the aircraft. Two other B-29s accompanied the Enola Gay to serve as observation and camera planes. Once the Enola Gay was airborne, Parsons added the final components to Little Boy. This was done because a number of the modified B-29s had crashed on takeoff, and there was some concern that a crash would cause a fully assembled bomb to detonate, wiping out the installation at Tinian.

The skies were clear, and the Enola Gay encountered no opposition while approaching the target. At 7:15 am (Tinian time) Parsons armed the weapon, and the Enola Gay ascended to an attack altitude of 31,000 feet (9,450 metres). A trio of B-29s had flown ahead of the strike force to perform weather reconnaissance over the primary (Hiroshima) and secondary (Kokura and Nagasaki) targets. The pilot of the Hiroshima mission radioed Tibbets that there was little cloud cover and that he should proceed to the primary target. Just after 8:00 am local time (9:00 am Tinian time), the crew of the Enola Gay sighted Hiroshima. At around 8:12 am Tibbets relinquished control of the aircraft to Ferebee, who began his bombing run. Ferebee’s aim point was the Aioi Bridge, a distinctive T-shaped span over the Ōta River. Tibbets ordered his crew to don their protective goggles, and at 8:15 am the bomb was released. Tibbets immediately put the Enola Gay into a sharp turn that, he hoped, would carry it beyond the bomb’s blast radius.

It took roughly 45 seconds for Little Boy to descend to an altitude of 1,900 feet (580 metres), at which point it exploded in the sky directly above Shima Hospital. Within a fraction of a second of the detonation, the temperature at ground level exceeded 7,000 °C (12,600 °F) and a powerful blast wave scoured the landscape. Out of a population of 343,000 inhabitants, some 70,000 people were killed instantly, and by the end of the year the death toll had surpassed 100,000. Two-thirds of the city area was destroyed. “Nuclear shadows” were all that remained of people who had been subjected to the intense thermal radiation. A massive mushroom cloud rose to a height of more than 40,000 feet (more than 12 km). Although less than 2 percent of the uranium-235 contained in Little Boy had achieved fission, the bomb was horrifying in its destructive power. The explosive yield was the equivalent of 15,000 tons of TNT. Sgt. Bob Caron, the Enola Gay’s tail gunner and the only member of the crew to directly observe the blast, described the scene as a “peep into hell.” A series of shockwaves rocked the Enola Gay as it departed the area, and at a distance of nearly 400 miles (640 km) the mushroom cloud was still visible. Upon returning to Tinian, after a flight of just over 12 hours, Tibbets was awarded the Distinguished Service Cross.

Later that day, Truman addressed the people of the United States:

Sixteen hours ago an American airplane dropped one bomb on Hiroshima, an important Japanese Army base. That bomb had more power than 20,000 tons of TNT. It had more than 2,000 times the blast power of the British “Grand Slam,” which is the largest bomb ever yet used in the history of warfare.

The Japanese began the war from the air at Pearl Harbor. They have been repaid many fold. And the end is not yet. With this bomb we have now added a new and revolutionary increase in destruction to supplement the growing power of our armed forces. In their present form these bombs are now in production, and even more powerful forms are in development.

It is an atomic bomb. It is a harnessing of the basic power of the universe. The force from which the sun draws its power has been loosed against those who brought war to the Far East.

Truman further noted, “We have spent two billion dollars on the greatest scientific gamble in history—and won.” Poet and author James Agee, writing in Time, offered something of a counterpoint to Truman’s speech:

The race had been won, the weapon had been used by those on whom civilization could best hope to depend but the demonstration of power against living creatures instead of dead matter created a bottomless wound in the living conscience of the race. The rational mind had won the most Promethean of its conquests over nature, and had put into the hands of common man the fire and force of the sun itself.

News of Hiroshima’s destruction was only slowly understood, and some Japanese officials argued that their own stalled atomic program had demonstrated how difficult it would be to create such a weapon. It was possible, they argued, that the bomb dropped on Hiroshima was the only one in the American arsenal. Other members of the Japanese government had been arguing for months in favour of a negotiated settlement, perhaps mediated by the Soviets. That window was abruptly closed on August 8, 1945, two days after the Hiroshima bombing, when the Soviet Union declared war against Japan.

She survived Hiroshima’s atomic bomb. Now she fears her story may be forgotten

Takano was at school about 12 miles from the bomb's hypocenter, or detonation point, on Aug 6, 1945. He still recalls seeing a flash “bigger than lightning” and hearing a “massive explosion — bang!”

He was sent home while debris fell from the sky. Seven years old, Takano said he tried to catch some of the objects as they showered down.

In the following days, he had a high fever and diarrhea. Although he recovered, Takano later endured many illnesses because of the exposure to radiation. He also lost his mother to cancer 19 years after the bomb dropped.

For those closer to the hypocenter, the damage came faster.

Tetsushi Yonezawa, who turns 86 on Sunday, was traveling on a busy train just 820 yards from the bomb.

Once on the military truck that rescued him and his mother, he recalls seeing people with broken bones protruding from their flesh and blood flowing from their ears.

One elderly woman “held an eyeball with her hand to avoid it falling out completely.”

“I think the next day the war ended,” Yonezawa said. “When I woke up, I saw my pillow had turned black. Looking carefully, I noticed that it was covered with my hair. I was so surprised, I touched my hair and it fell onto the sheets. I ran to my mother and she had also lost her hair. Both of us lost all our hair on the same day.”

His mother’s symptoms worsened — including bleeding gums and purple spots all over her skin. She was dead less than a month later, Yonezawa said.

“I think that the sad thing is that that legacy has died somewhat,” said Dan Smith, director of the Stockholm International Peace Research Institute. “There are now a number of developments happening in the nuclear arms field, which are seeming to receive no public attention whatsoever.”

There are an estimated 13,400 nuclear weapons in existence globally, according to the institute. The vast majority of them belong to the United States and Russia, with more than 6,000 weapons each.

Although it's far fewer than the peak of about 65,000 weapons in the 1980s — a product of the Cold War — warheads today are far more powerful.

An exchange of fewer than 1,000 nuclear weapons could kill as many as 100 million people in a matter of hours, said Daryl Kimball, executive director of the nonpartisan Arms Control Association, based in Washington.

“A nuclear war cannot be won and must never be fought,” he said. “It's in everyone's interest to reduce the risk of this ever happening.”

Yet global tensions are at their highest since the end of the Cold War, Kimball said. Recent years have seen mounting threats among the U.S., Russia, North Korea and China. One nonproliferation treaty between the U.S. and Russia is also set to expire in February.

Even countries with smaller arsenals, such as India and Pakistan, with fewer than 200 warheads each, have increasingly been at odds, Kimball said.

“There needs to be a combination of leadership and creativity to head off additional competition and arms racing,” he said.

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Yet, the U.S. has committed more than $1.7 trillion in the coming years to upgrading its arsenal, and Russia has similar plans, experts say.

The argument for the investment is less about the practical defense the weapons offer and more about technological developments and support for the economy, said Robert Jacobs, a history professor at the Hiroshima Peace Institute.

“These are militarily useless weapons,” Jacobs said. “The risks of starting down that path are uncontrollable.”

Amid the global economic challenges sparked by the coronavirus pandemic, experts say that now may be the moment to question whether governments should be funding military technologies designed for crises of a previous generation.

“No matter how much money we spend to harden our infrastructure against a terrorist threat, that does nothing to defend us against a tiny invisible virus,” Kimball said. “I think this is the time to seriously rethink the role of nuclear weapons.”

Watch the video: The Day Japan Surrendered, Ending WWII. NBC News