How many times did the US experiment before dropping the atomic bomb in Japan?

How many times did the US experiment before dropping the atomic bomb in Japan?

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I know it is at least once. They performed a test called Trinity.

Was it the only one?

Yes, it was the only test.

The plutonium (implosion) bomb design was only tested that one time before being used on Nagasaki. The uranium (gun) bomb design was entirely untested (*) when used on Hiroshima.

(*): "Untested" / "tested only once" refers to a complete "device" leading to a runaway chain reaction. They have been testing the heck out of the individual components, and have been conducting many tests to figure out at which point the runaway chain reaction would occur so they could build a device that would neither "fizzle" (start chain reaction too soon and go "pop" instead of "boom" because the device destroys itself prematurely) nor fail to enter chain reaction at all.

The uranium (gun) design was considered to be so simple that the chance of malfunction was minimal and did not require testing. Besides, they only had enough U235 for the one bomb anyway.

Back to Hiroshima: Why Dropping the Bomb Saved Ten Million Lives

President Barack Obama's forthcoming visit to Japan has revived interest in the debate over the decision to drop the atomic bomb on Hiroshima.

For me, the matter is crystal clear, and the moral and ethical issues are straightforward. The destruction caused by those bombs was horrific beyond description, and Hiroshima should be always in the minds of policy makers, to prevent nightmares like that ever occurring again.

But let us be clear. In the context of 1945, using the atomic bombs saved lives - millions of them.

So was the United States right to use the bombs? Unquestionably.

I stress that because of the misinformation that is often circulated concerning alleged Japanese plans to surrender even without the bombs.

At some point in these debates, you undoubtedly hear the following gem quoted, from the United States Strategic Bombing Survey (SBS):

"Based on a detailed investigation of all the facts, and supported by the testimony of the surviving Japanese leaders involved, it is the Survey's opinion that certainly prior to 31 December 1945, and in all probability prior to 1 November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated."

This statement is utterly tendentious. The SBS survey did indeed report as much, but wholly for their own partisan reasons. Namely, they desperately wanted to preserve the existence of a separate U.S. Air Force after the war, and so they needed to minimize the effects of the atomic bombs. They made many such claims that were not, in fact, right.

The statement about surrender was never accurate, or close to accurate, and it would not be upheld by many reputable historians today.

Much of the confusion involves the definition of terms like "surrender." The Japanese did indeed float various schemes to end the war, but on terms that were totally unacceptable to any Allied power. Among other things, these schemes involved no occupation, no dismantling of militarism or imperialism, and no punishment of war criminals. No retaliation for the savage crimes in China, the East Indies and elsewhere. Then, after a hiatus of a couple years, Japan would launch the next wave of aggression. They were clearly not talking "surrender" in any sense of the term we might recognize.

Let me give an analogy. Suppose that in late 1944, Nazi Germany had suggested peace terms that involved keeping their existing borders as they were at that point. The regime would remain in place indefinitely, and presumably mass killings would continue. Would anyone on the Allied side have tolerated such an outcome?

No atomic bombs, no Japanese surrender. We now have plenty of testimony on both sides to make that absolutely clear. So what were the alternatives? What if the war had carried on through, say, late 1946?

Invasion was impossible. The planned U.S. invasion of Kyushu (Operation Olympic) in late 1945 would have been one of the greatest catastrophes in military history, not least because the Japanese knew precisely where and when it was coming. They were exceedingly well prepared, with fleets of thousands of suicide bombers. The planned follow-up attack on Honshu in 1946 (Coronet) would never have happened because the U.S. military would have effectively have been destroyed. Quite apart from the Japanese, the great Typhoon of October 1945 would have smashed the U.S. invasion fleet before it got close to the beaches.

The sometimes quoted estimate of 30-40,000 U.S. fatalities in such an invasion is a joke, a figure cooked to persuade the administration that General MacArthur should be allowed to get away with a piece of monstrous stupidity.

The only realistic U.S. response at this stage would have been to firebomb the 1946 rice harvest. The resulting famine would have killed at least several million, by credible estimates. Reinforcing that campaign would have been further fire raids on Japanese cities, like the one on Tokyo in March 1945 that killed one hundred thousand people. That's not quite in the league of the atomic bomb - but it is very close.

Meanwhile, there is the point that for me is quite decisive. When we consider the toll of not dropping the bombs, always remember the many thousands of civilians who were dying under Japanese occupation in China and Indonesia throughout 1945, and we should continue counting the deaths that would have occurred at that rate through 1946. Nothing was going to stop that short of the total destruction of Japanese war-making capacity.

Add to this the murder of all Allied POWs in Japanese hands, as the Japanese had ordered in the event of a direct attack on the mainland. Put those figures together, together with likely Japanese fatalities, you get about ten million dead - and that's a conservative figure. The vast majority of those additional deaths would have been East and South-East Asians, mainly Japanese and Chinese.

The political consequences are also horrible to contemplate. If it had turned out that tens of thousands of American soldiers were being killed while the U.S. was failing to use a war-winning weapon, the Secret Service would probably have taken the lead in assassinating Harry Truman.

I truly understand why well-intentioned people would like to think that Japan was on the verge of surrender, so that the nuclear option could have been avoided. It would have made the ethical debate so clean and simple. But no, sorry, that was just not a viable option, and much harder decisions had to be made.

Philip Jenkins is Distinguished Professor of History at Baylor University and Co-Director of the Program on Historical Studies of Religion at theInstitute for Studies of Religion. He is the author of many books, includingThe Great and Holy War: How World War I Became a Religious Crusade.

How many times did the US experiment before dropping the atomic bomb in Japan? - History

(Trinity Test Site, July 16, 1945)
Events > Dawn of the Atomic Era, 1945

  • The War Enters Its Final Phase, 1945
  • Debate Over How to Use the Bomb, Late Spring 1945
  • The Trinity Test, July 16, 1945
  • Safety and the Trinity Test, July 1945
  • Evaluations of Trinity, July 1945
  • Potsdam and the Final Decision to Bomb, July 1945
  • The Atomic Bombing of Hiroshima, August 6, 1945
  • The Atomic Bombing of Nagasaki, August 9, 1945
  • Japan Surrenders, August 10-15, 1945
  • The Manhattan Project and the Second World War, 1939-1945

Until the atomic bomb could be tested, doubt would remain about its effectiveness. The world had never seen a nuclear explosion before, and estimates varied widely on how much energy would be released. Some scientists at Los Alamos continued privately to have doubts that it would work at all. There was only enough weapons-grade uranium available for one bomb, and confidence in the gun-type design was high, so on July 14, 1945, most of the uranium bomb ("Little Boy") began its trip westward to the Pacific without its design having ever been fully tested. A test of the plutonium bomb seemed vital, however, both to confirm its novel implosion design and to gather data on nuclear explosions in general. Several plutonium bombs were now "in the pipeline" and would be available over the next few weeks and months. It was therefore decided to test one of these.

Robert Oppenheimer chose to name this the "Trinity" test, a name inspired by the poems of John Donne. The site chosen was a remote corner on the Alamagordo Bombing Range known as the "Jornada del Muerto," or "Journey of Death," 210 miles south of Los Alamos. The elaborate instrumentation surrounding the site was tested with an explosion of a large amount of conventional explosives on May 7. Preparations continued throughout May and June and were complete by the beginning of July. Three observation bunkers located 10,000 yards north, west, and south (right) of the firing tower at ground zero would attempt to measure key aspects of the reaction. Specifically, scientists would try to determine the symmetry of the implosion and the amount of energy released. Additional measurements would be taken to determine damage estimates, and equipment would record the behavior of the fireball. The biggest concern was control of the radioactivity the test device would release. Not entirely content to trust favorable meteorological conditions to carry the radioactivity into the upper atmosphere, the Army stood ready to evacuate the people in surrounding areas.

On July 12, the plutonium core was taken to the test area in an army sedan (left). The non-nuclear components left for the test site at 12:01 a.m., Friday the 13th. During the day on the 13th, final assembly of the "Gadget" (as it was nicknamed) took place in the McDonald ranch house. By 5:00 p.m. on the 15th, the device had been assembled and hoisted atop the 100-foot firing tower. Leslie Groves, Vannevar Bush, James Conant, Ernest Lawrence, Thomas Farrell, James Chadwick, and others arrived in the test area, where it was pouring rain. Groves and Oppenheimer, standing at the S-10,000 control bunker, discussed what to do if the weather did not break in time for the scheduled 4:00 a.m. test. To break the tension, Fermi began offering anyone listening a wager on "whether or not the bomb would ignite the atmosphere, and if so, whether it would merely destroy New Mexico or destroy the world." Oppenheimer himself had bet ten dollars against George Kistiakowsky's entire month's pay that the bomb would not work at all. Meanwhile, Edward Teller was making everyone nervous by applying liberal amounts of sunscreen in the pre-dawn darkness and offering to pass it around. At 3:30, Groves and Oppenheimer pushed the time back to 5:30. At 4:00, the rain stopped. Kistiakowsky and his team armed the device shortly after 5:00 and retreated to S-10,000. In accordance with his policy that each observe from different locations in case of an accident, Groves left Oppenheimer and joined Bush and Conant at base camp. Those in shelters heard the countdown over the public address system, while observers at base camp picked it up on an FM radio signal.

During the final seconds, most observers laid down on the ground with their feet facing the Trinity site and simply waited. As the countdown approached one minute, Isidore Rabi said to the man lying next to him, Kenneth Griesen, "Aren't you nervous?" "Nope" was Griesen's reply. As Groves later wrote, "As I lay there in the final seconds, I thought only of what I would do if the countdown got to zero and nothing happened." Conant said he never knew seconds could be so long. As the countdown reached 10 seconds, Griesen suddenly blurted out to his neighbor Rabi, "Now I'm scared." Three, two, one, and Sam Allison cried out, "Now!"

At precisely 5:30 a.m. on Monday, July 16, 1945, the nuclear age began. While Manhattan Project staff members watched anxiously, the device exploded over the New Mexico desert, vaporizing the tower and turning the asphalt around the base of the tower to green sand. Seconds after the explosion came a huge blast wave and heat searing out across the desert. No one could see the radiation generated by the explosion, but they all knew it was there. The steel container "Jumbo," weighing over 200 tons and transported to the desert only to be eliminated from the test, was knocked ajar even though it stood half a mile from ground zero. As the orange and yellow fireball stretched up and spread, a second column, narrower than the first, rose and flattened into a mushroom shape, thus providing the atomic age with a visual image that has become imprinted on the human consciousness as a symbol of power and awesome destruction.

The most common immediate reactions to the explosion were surprise, joy, and relief. Lawrence was stepping from his car when, in his words, everything went "from darkness to brilliant sunshine in an instant" he was "momentarily stunned by the surprise." (Click here to read Lawrence's thoughts on the Trinity test.) A military man was heard to exclaim, "The long-hairs have let it get away from them!" Hans Bethe , who had been looking directly at the explosion, was completely blinded for almost half a minute. Norris Bradbury reported that "the atom bomb did not fit into any preconceptions possessed by anybody." The blast wave knocked Kistiakowsky (who was over five miles away) to the ground. He quickly scrambled to his feet and slapped Oppenheimer on the back, saying, "Oppie, you owe me ten dollars." The physicist Victor Weisskopf reported that "our first feeling was one of elation." The word Isidor Rabi used was "jubilant." Within minutes, Rabi was passing around a bottle of whiskey. At base camp, Bush, Conant, and Groves shook hands. Rabi reported watching Oppenheimer arrive at base camp after the test:

When they met, Groves said to Oppenheimer, "I am proud of you." Groves's assistant, Thomas Farrell, remarked to his boss that "the war is over," to which Groves replied, "Yes, after we drop two bombs on Japan." (Click here to read Groves's observations of the Trinity test [pdf].) Probably the most mundane response of all was Fermi's: he had calculated ahead of time how far the blast wave might displace small pieces of paper released into it. About 40 seconds after the explosion, Fermi stood, sprinkled his pre-prepared slips of paper into the atomic wind, and estimated from their deflection that the test had released energy equivalent to 10,000 tons of TNT. The actual result as it was finally calculated -- 21,000 tons (21 kilotons) -- was more than twice what Fermi had estimated with this experiment and four times as much as had been predicted by most at Los Alamos.

Soon shock and euphoria gave way to more sober reflections. Rabi reported that after the initial euphoria, a chill soon set in on those present. The test director, Kenneth Bainbridge, called the explosion a "foul and awesome display" and remarked to Oppenheimer, "Now we are all sons of bitches." Expressions of horror and remorse are especially common in the later writings of those who were present. Oppenheimer wrote that the experience called to his mind the legend of Prometheus, punished by Zeus for giving man fire, and said also that he thought fleetingly of Alfred Nobel's vain hope that dynamite would end wars. Most famously, Oppenheimer later recalled that the explosion had reminded him of a line from the Hindu holy text, the Bhagavad-Gita: "Now I am become Death, the destroyer of worlds." The terrifying destructive power of atomic weapons and the uses to which they might be put were to haunt many of the Manhattan Project scientists for the remainder of their lives.

The success of the Trinity test meant that both types of bombs -- the uranium design, untested but thought to be reliable, and the plutonium design, which had just been tested successfully -- were now available for use in the war against Japan. Little Boy, the uranium bomb, was dropped first at Hiroshima on August 6, while the plutonium weapon, Fat Man, followed three days later at Nagasaki on August 9. Within days, Japan offered to surrender.

  • The War Enters Its Final Phase, 1945
  • Debate Over How to Use the Bomb, Late Spring 1945
  • The Trinity Test, July 16, 1945
  • Safety and the Trinity Test, July 1945
  • Evaluations of Trinity, July 1945
  • Potsdam and the Final Decision to Bomb, July 1945
  • The Atomic Bombing of Hiroshima, August 6, 1945
  • The Atomic Bombing of Nagasaki, August 9, 1945
  • Japan Surrenders, August 10-15, 1945
  • The Manhattan Project and the Second World War, 1939-1945

Previous Next

21 Surprising Facts About the Atomic Bomb Attacks on Japan

Seventy years later, the U.S. atomic bomb attacks on Hiroshima and Nagasaki remain, thankfully, the only time nuclear weapons have been used in active warfare. Some of what happened will amaze you, including the man who survived both attacks.

21. The Enola Gay Was Named After the Pilot's Mother

The Enola Gay was the Boeing B-29 Superfortress bomber plane which dropped the atomic bomb on Hiroshima on Aug. 6, 1945. It was piloted by Colonel Paul Tibbets, a 30-year-old colonel from Illinois. He named the plane in tribute to his mother, Enola Gay Tibbets.

20. The 1st Target Was Decided an Hour Before the Drop

The good weather conditions over Hiroshima sealed the city's fate.That was determined by a weather plane that buzzed over Hiroshima. On the ground, a yellow alert rings out for 22 minutes. Many civilians ignore it, unperturbed by the familiar sight of a single B-29 plane flying over the city. The weather plane sends a coded message to Enola Gay, advising that Hiroshima is to be the primary target. Tibbets notifies his crew over the intercom and the plane sets course.

19. 60 million degrees

That was the Fahrenheit temperature in Hiroshima at ground zero upon detonation.

18. Up to 246,000 Dead

Up to 166,000 were killed in Hiroshima and 80,000 in Nagasaki died as a result of the two atomic bomb drops. About half were killed on the first day the rest died of horrific injuries caused by radiation poisoning in the days, weeks and months that followed.

17. 'My God, What Have We Done?'

That's what Enola Gay crewman Captain Robert A. Lewis said, and later recorded in his notebook, after the bomb was dropped.

Radar operator Joe Stiborik remembered the crew sitting in stunned silence on the return flight. The only words he recollected hearing were Lewis's "My God, what have we done." He explained, "I was dumbfounded. Remember, nobody had ever seen what an A-bomb could do before. Here was a whole damn town nearly as big as Dallas, one minute all in good shape and the next minute disappeared and covered with fires and smoke. . There was almost no talk I can remember on our trip back to the base. It was just too much to express in words, I guess. We were all in a kind of state of shock. I think the foremost thing in all our minds was that this thing was going to bring an end to the war and we tried to look at it that way."

16. The Bomb Was Armed in Mid-Air

At the hangar on Tinian Island, where the bomb was delivered by the USS Indianapolis, Little Boy is wheeled carefully out of its hanger and toward the Enola Gay. But Captain William "Deak" Parsons, an atomic ballistics expert, is concerned.

Two B-29 planes have exploded on take-off in the last 24 hours. If the B-29 carrying Little Boy explodes, the consequences could be catastrophic. He takes a radical decision &ndash both he and his colleague, Lieutenant Morris Jeppson, will arm the bomb in the air. It is a feat not attempted outside a laboratory.

15. Nagasaki Was a Secondary Target

The Enola Gay participated in the second atomic attack as the weather reconnaissance aircraft for the primary target of Kokura. Clouds and drifting smoke resulted in Nagasaki being bombed instead.

14. The Plane That Dropped the 2nd Bomb Was Names 'Bockscar'

The B-29 that dropped the "Fat Man" bomb on Nagasaki was under the command of Captain Frederick C. Bock. The name "Bockscar" is a pun on his name.

13. Most of the Men Who Delivered the Bomb Were Already Dead When the Bomb Was Dropped

The parts for the atomic bomb were delivered to the island of Tinian by the USS Indianapolis, a heavy cruiser which picked up the parts in San Francisco, stopped by Pearl Harbor and advanced on to Tinian. But after dropping the parts off, the Indianapolis was sunk by torpedoes from a Japanese submarine on July 30. Because its mission was secret, the loss of the Indianapolis wasn't discovered for almost four days. Of the 1,196 crewmen, about 300 went down with the ship and about 575 died while in the water -- many by shark attacks. It is believed to be the largest attack by sharks on humans in history. Only 317 survived to hear about the bombings.

12. A Honeymoon Helped Kyoto Escape Destruction

The beautiful Japanese city of Kyoto was initially considered for the second bomb, but -- as legend has it -- Secretary of War Henry Stimson asked for it to be removed from the target list because he'd been there on his honeymoon.

11. The Enola Gay Crew Had Cyanide Tablets

If the mission failed, they were not to be taken alive.

10. The 2 Bombs Were Completely Different

The Aug. 6 bomb that was dropped on Hiroshima was named &ldquoLittle Boy,&rdquo and it was uranium-based. The Aug. 9 bomb that was dropped on Nagasaki was named &ldquoFat Man,&rdquo and it was plutonium-based. Little Boy&rdquo was about 10 feet long and weighed more than four metric tons. &ldquoFat Man&rdquo was even bigger, at about 11.5 feet long and 4.5 tons.

9. This Man Survived Both Bomb Attacks

Tsutomu Yamaguchi was a 39-year-old businessman who lived in Nagasaki. Yamaguchi was in Hiroshima on business for his employer Mitsubishi Heavy Industries when the city was bombed at 8:15 am, on August 6, 1945. The explosion ruptured his eardrums, blinded him temporarily, and left him with serious burns over the left side of the top half of his body.

He returned to Nagasaki the following day, and despite his wounds, he returned to work on August 9, the day of the second atomic bombing. That morning he was telling his supervisor how one bomb had destroyed the city, to which his supervisor told him that he was crazy, and at that moment the Nagasaki bomb detonated. He was not injured in that explosion.

Yamaguchi died of stomach cancer on January 4, 2010, at the age of 93.

8. The Father of the Bomb Campaigned Against Nuclear Proliferation

J. Robert Oppenheimer, the key figure of the Manhattan Project, which developed the bomb in the New Mexico desert, said the detonation of the bombs reminded him of words from the Bhagavad Gita: "Now I am become Death, the destroyer of worlds." After the war he became a chief advisor to the newly created United States Atomic Energy Commission and used that position to lobby for international control of nuclear power to avert nuclear proliferation and an arms race with the Soviet Union. After provoking the ire of many politicians with his outspoken opinions during the Second Red Scare, he had his security clearance revoked. He continued his anti-nuclear work until his death in 1967 of throat cancer at age 62.

7. Truman Was Prepared to Drop More Bombs

U.S. President Harry Truman knew an invasion of Tokyo would cause massive U.S. casualties. With the new nuclear technology, he was prepared to use it. "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," he said in a news release after the bombing of Hiroshima. "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."

6. Emperor Hirohito's Surrender on Radio Was the 1st Time His Voice Was Heard Publicly

That's right, in power since 1926, Hirohito allowed a recording of the his surrender speech to be broadcast over the radio on August 15, 1945 (the first time the Emperor was heard on the radio by the Japanese people). He spoke in classical Japanese, making it difficult for some citizens to fully comprehend what he is saying. Despite two devastating attacks on the country, many people are shocked &ndash the Japanese Empire has maintained it would be more noble to endure annihilation than surrender to the enemy. Japan&rsquos war minister had attempted suicide and dies the following day. Many thought the emperor would order the mass suicide of all citizens rather than surrender. He did not.

5. Nagasaki and Hiroshima Are Not Radioactive Today

That's because the bombs were exploded a couple of thousand feet above the cities instead of detonating on the ground.

4. A Witness to the Hiroshima Attack Won the Boston Marathon

Shigeki Tanaka was 13 and living 20 miles from Hiroshima when he saw the bombing. Six years later, he became the first Japanese person to win the Boston Marathon, The victory in 1951 was a landmark moment in restoring the war-shattered country's dignity and honor. After World War II, Japanese athletes were barred from the 1948 Summer Olympics in London and from all major international competitions around the world.

3. A Bonsai Tree Planted in 1626 Survived the Hiroshima Attack

The nursery that housed the tree was less than two miles from the bomb blast site. It now resides in Washington, D.C. at the National Arboretum.

2. The Hiroshima Peace Memorial Museum Is One of the Most Moving Places in the World

Located in Hiroshima Peace Memorial Park, in central Hiroshima, it is not only dedicated to documenting the World War II atomic bombing, but has the additional aim of promoting world peace. Visited by a million people a year, it's surprisingly a place of hope and well worth the long train ride from Tokyo.

1. Paper Lanterns Signify the Afterlife

The thousands of colorful paper lanterns released on the city's Motoyasu River symbolized the spiritual journey of those killed by the bomb.

American Experience

Sixteen hours ago an American airplane dropped one bomb on Hiroshima and destroyed its usefulness to the enemy. That bomb had more power than 20,000 tons of TNT. It had more than two thousand 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.

Before 1939, it was the accepted belief of scientists that it was theoretically possible to release atomic energy. But no one knew any practical method of doing it. By 1942, however, we knew that the Germans were working feverishly 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. We may be grateful to Providence that the Germans got the V-1's and V-2's late and in limited quantities and even more grateful that they did not get the atomic bomb at all.

The batle of the laboratories 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.

Beginning in 1940, before Pearl Harbor, scientific knowledge useful in was pooled between the United States and Great Britain, and many priceless helps to our victories have come from that arrangement. 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.

The United States had available the large number of scientists of distinction in the many needed areas of knowledge. It had the tremendous industrial and financial resources necessary for the project and they could be devoted to it without undue impairment of other vital war work. In the United States the laboratory work and the production plants, on which a substantial start had already been made, would be out of reach of enemy bombing, while at that time Britain was exposed to constant air attack and was still threatened with the possibility of invasion. For these reasons Prime Minister Churchill and President Roosevelt agreed that it was wise to carry on the project here. We now have two great plants and many lesser works devoted to the production of atomic power. Employment during peak construction numbered 125,000 and over 65,000 individuals are even now engaged in operating the plants. Many have worked there for two and a half years. Few know what they have been producing. They see great quantities of material going in and they see nothing coming out of these plants, for the physical size of the explosive charge is exceedingly small. We have spent two billion dollars on the greatest scientific gamble in history -- and won.

But the greatest marvel is not the size of the enterprise, its secrecy, nor its cost, but the achievement of scientific brains in putting together infinitely complex pieces of knowledge held by many men in different fields of science into a workable plan. And hardly less marvelous has been the capacity of industry to design and of labor to operate, the machines and methods to do things never done before so that the brainchild of many minds came forth in physical shape and performed as it was supposed to do. Both science and industry worked under the direction of the United States Army, which achieved a unique success in managing so diverse a problem in the advancement of knowledge in an amazingly short time. It is doubtful if such another combination could be got together in the world. What has been done is the greatest achievement of organized science in history. It was done under pressure and without failure.

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.

It was to spare the Japanese people from utter destruction 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 such number that and power as they have not yet seen and with the fighting skill of which they are already well aware.

The Secretary of War, who has kept in personal touch with all phases of the project, will immediately make public a statement giving further details.

His statement will give facts concerning the sites at Oak Ridge near Knoxville, Tennessee, and at Richland, near Pasco, Washington, and an installation near Santa Fe, New Mexico. Although the workers at the sites have been making materials to be used producing the greatest destructive force in history they have not themselves been in danger beyond that of many other occupations, for the utmost care has been taken of their safety.

The fact that we can release atomic energy ushers in a new era in man's understanding of nature's forces. Atomic energy may in the future supplement the power that now comes from coal, oil, and falling water, but at present it cannot be produced on a bases to compete with them commercially. Before that comes there must be a long period of intensive research. It has never been the habit of the scientists of this country or the policy of this government to withhold from the world scientific knowledge. Normally, therefore, everything about the work with atomic energy would be made public.

But under the present circumstances it is not intended to divulge the technical processes of production or all the military applications. Pending further examination of possible methods of protecting us and the rest of the world from the danger of sudden destruction.

I shall recommend that the Congress of the United States consider promptly the establishment of an appropriate commission to control the production and use of atomic power within the United States. I shall give further consideration and make further recommendations to the Congress as to how atomic power can become a powerful and forceful influence towards the maintenance of world peace.

Source: Harry S. Truman Library, "Army press notes," box 4, Papers of Eben A. Ayers.


All belligerents in World War II sought to develop powerful and devastating weaponry. As early as 1939, German scientists had discovered how to split uranium atoms, the technology that would ultimately allow for the creation of the atomic bomb. Albert Einstein, who had emigrated to the United States in 1933 to escape the Nazis, urged President Roosevelt to launch an American atomic research project, and Roosevelt agreed to do so, with reservations. In late 1941, the program received its code name: the Manhattan Project . Located at Los Alamos, New Mexico, the Manhattan Project ultimately employed 150,000 people and cost some $2 billion. In July 1945, the project’s scientists successfully tested the first atomic bomb.

In the spring of 1945, the military began to prepare for the possible use of an atomic bomb by choosing appropriate targets. Suspecting that the immediate bomb blast would extend over one mile and secondary effects would include fire damage, a compact city of significant military value with densely built frame buildings seemed to be the best target. Eventually, the city of Hiroshima, the headquarters of the Japanese Second Army, and the communications and supply hub for all of southern Japan, was chosen. The city of Kokura was chosen as the primary target of the second bomb, and Nagasaki, an industrial center producing war materiel and the largest seaport in southern Japan, was selected as a secondary target.

The Enola Gay , a B-29 bomber named after its pilot’s mother, dropped an atomic bomb known as “Little Boy” on Hiroshima at 8:15 a.m. A huge mushroom cloud rose above the city. Survivors sitting down for breakfast or preparing to go to school recalled seeing a bright light and then being blown across the room. The immense heat of the blast melted stone and metal, and ignited fires throughout the city. One man later recalled watching his mother and brother burn to death as fire consumed their home. A female survivor, a child at the time of the attack, remembered finding the body of her mother, which had been reduced to ashes and fell apart as she touched it. Two-thirds of the buildings in Hiroshima were destroyed. Within an hour after the bombing, radioactive “black rain” began to fall. Approximately seventy thousand people died in the original blast. The same number would later die of radiation poisoning. When Japan refused to surrender, a second atomic bomb, named Fat Man, was dropped on Nagasaki on August 9, 1945. At least sixty thousand people were killed at Nagasaki. Kokura, the primary target, had been shrouded in clouds on that morning and thus had escaped destruction. It is impossible to say with certainty how many died in the two attacks the heat of the bomb blasts incinerated or vaporized many of the victims.

According to estimates, the atomic bombs dropped on Hiroshima and Nagasaki (a) together killed anywhere from 125,000 to over 250,000 people. The so-called Genbaku (A-Bomb) Dome, now the Hiroshima Peace Memorial, was the only building left standing near the Hiroshima bomb’s hypocenter (b).

The decision to use nuclear weapons is widely debated. Why exactly did the United States deploy an atomic bomb? The fierce resistance that the Japanese forces mounted during their early campaigns led American planners to believe that any invasion of the Japanese home islands would be exceedingly bloody. According to some estimates, as many as 250,000 Americans might die in securing a final victory. Such considerations undoubtedly influenced President Truman’s decision. Truman, who had not known about the Manhattan Project until Roosevelt’s death, also may not have realized how truly destructive it was. Indeed, some of the scientists who had built the bomb were surprised by its power. One question that has not been fully answered is why the United States dropped the second bomb on Nagasaki. As some scholars have noted, if Truman’s intention was to eliminate the need for a home island invasion, he could have given Japan more time to respond after bombing Hiroshima. He did not, however. The second bombing may have been intended to send a message to Stalin, who was becoming intransigent regarding postwar Europe. If it is indeed true that Truman had political motivations for using the bombs, then the destruction of Nagasaki might have been the first salvo of the Cold War with the Soviet Union. And yet, other historians have pointed out that the war had unleashed such massive atrocities against civilians by all belligerents—the United States included—that by the summer of 1945, the president no longer needed any particular reason to use his entire nuclear arsenal.

A New York Times exclusive

In gratitude for Laurence’s services, the Army tipped the top management of the Times on August 2 about the impending use of the bomb against Japan, so the paper could prepare.

On Aug. 6, 1945, the world first learned about the atomic bomb when the United States dropped it on the Japanese city of Hiroshima. Three days later, the Army Air Corps struck again, this time at Nagasaki. On board one of the aircraft on Aug. 9 was Laurence.

William Laurence (left) in the Pacific on the eve of the bombings. US Air Force

As the official journalistic witness to the Manhattan Project, he was now the first American civilian to observe the use of the terrible new weapon in war. His detailed, poetic narrative (which appeared in the Times a month later) began simply: “We are on our way to bomb the mainland of Japan.”

As the hours ticked by en route to the target, Laurence mused in print about the morality of setting out to wipe an entire city off the map.

He asked himself if he felt any pity for the “poor devils” who would be obliterated by the bomb. His answer: “Not when one thinks of Pearl Harbor and of the Death March on Bataan.” In other words, he figured – as did many Americans – that the “Japs” had it coming.

Then, over Nagasaki, Laurence and the crew beheld the existential chaos unleashed by splitting the atom:

“Awe-struck, we watched it shoot upward like a meteor coming from the earth instead of from outer space, becoming ever more alive as it climbed skyward through the white clouds. It was no longer smoke, or dust, or even a cloud of fire. It was a living thing, a new species of being, born right before our incredulous eyes.

At one stage of its evolution, covering millions of years in terms of seconds, the entity assumed the form of a giant square totem pole, with its base about three miles long, tapering off to about a mile at the top. Its bottom was brown, its center was amber, its top white. But it was a living totem pole, carved with many grotesque masks grimacing at the earth…

It kept struggling in an elemental fury, like a creature in the act of breaking the bonds that held it down. In a few seconds it had freed itself from its gigantic stem and floated upward with tremendous speed, its momentum carrying into the stratosphere to a height of about 60,000 feet…

As the mushroom floated off into the blue it changed its shape into a flowerlike form, its giant petal curving downward, creamy white outside, rose-colored inside. It still retained that shape when we last gazed at it from a distance of about 200 miles.”

How many times did the US experiment before dropping the atomic bomb in Japan? - History

Was the dropping of the atomic bombs ethically permissible or not? A public spiritual message from Master Ryuho Okawa, the CEO and founder of Happy Science, shed light on the ethical controversy concerning World War II, a debate that continues to this day. Former U.S. President Truman was the man who decided to drop the atomic bombs on Japan. Former U.S. President Franklin Roosevelt was the one who launched the Manhattan Project to develop the A-bomb in the first place.

In this shocking spiritual message, the spirits of both former presidents truthfully speak about WWII. It offers important lessons for reconsidering the Japanese and American historical viewpoints as well as for jointly creating world peace.

Giving a Fresh Look at Modern History in Order to Create Strong U.S. – Japan Relations That Will Foster World Peace.

In the United States, students learn at school: one million American soldiers would have died without the use of the atomic bombs. The war against Japan was a victory for freedom and democracy, which justified the use of the atomic bombs.

However, did this explanation really justify the use of the atomic bombs? Right before the atomic bombs were dropped in Hiroshima and Nagasaki, the U.S. had conducted indiscriminate bombings on more than 200 Japanese cities, and it had already claimed the lives of 330,000 civilians, even though Japan had already communicated via the Soviet Union its intention to surrender and the end of war was just a matter of time. Even U.S. Generals MacArthur and Eisenhower opposed the idea of using the atomic bombs, and they claimed there was no military benefit.

Furthermore, why did the U.S. target Japan first? In a spiritual message, former President Truman said, “I dropped two atomic bombs as an ‘experiment,’” which ended up claiming the lives of as many as 200,000 civilians. His spirit indicated that since he did not consider the Japanese were human beings, his actions did not constitute war crimes.

In his comments, one can see that there was racism based on the idea of white supremacy. One of the causes of the war that Japan fought for was “liberating Asia from Western colonialism and abolishing racial discrimination.” Before the East Asian War, the world had only 69 independent countries, but now there are nearly 200. Although Japan lost the war, the liberation of colonies and the abolishment of racial discrimination were successfully realized.

In the U.S., the war between America and Japan has been explained as “a war to overthrow Japanese fascism.” But that is not actually true. As you can see from the excerpts of the chief editor’s column“,

“Japan was forced to fight a “war of self-defence” against looming white supremacist colonial rule and communist expansion.
After the Russo-Japanese War, Japan and America came into direct conflict over their interests on the continent of China. In the Second Sino-Japanese War from 1937, America supported the Kuomintang and in actuality entered a “war by proxy” against Japan. Japan was driven into a corner by such things as the post-Great Depression change to bloc economies, the formation of the anti-Japanese ABCD encirclement, and American oil embargoes, and this led to the outbreak of war between Japan and the U.S. in 1941.”

In the United States, some media labels Mr. Abe as “a right-wing nationalist”. Reporters criticize his revisionist views, and discuss the outrage in China as well as South Korea.

However, in order to stop China’s hegemonic ambitions, the U.S. now stands at a crossroad. Will it accept a strong Japan or not?

While the winners always write history, that type of perception of history does not necessarily satisfy the standards of God’s justice.

Through series upon series of spiritual messages, Master Okawa has revealed justice throughout world history by discovering where great past figures are now, and what they have been doing since their deaths.

In order to create truly constructive U.S. – Japanese relations that will serve to create world peace, we see it is necessary to re-examine history up until the Second World War with a fresh perspective. The spiritual messages from Truman show a way to overcome the past conflict between the U.S. and Japan, and give us the opportunity to create strong relations that will serve for the realization of world peace.

Extracts from this public, spiritual message follow (note 1).

Note 1: These spiritual messages were channelled through Ryuho Okawa. However, please note that because of his high level of enlightenment, his way of receiving spiritual messages is fundamentally different from other psychic mediums who undergo trances and are completely taken over by the spirits they are channeling.

Each human soul is made up of six soul siblings, one of whom acts as the guardian spirit of the person living on earth. People living on earth are connected to their guardian spirits at the innermost subconscious level. They are a part of people’s very souls, and therefore, exact reflections of their thoughts and philosophies.

However, please note that these spiritual messages are opinions of the individual spirits and may contradict the ideas or teachings of the Happy Science Group.

Read more on this>>

Answers to questions on spiritual messages part 1

Answers to questions on spiritual messages part 2

Let’s Explore Who Is “Responsible for Dropping the A-bombs”!

Today’s theme is whether the atomic bombings were a crime against humanity. No one has ever investigated this subject, and there may well be no moralist, religious leader, or thinker with the responsibility enough to answer this question.

After the A-bombs were dropped, I believe that Einstein and many other scientists who were involved in building the atomic bombs threw themselves into the peace movement. The scientists, who actually built the bomb, became opposed to it, because its use generated political problems.

Harry S. Truman gave the order to drop the A-bombs. He was the vice-president who succeeded to the presidency when Franklin Roosevelt died in April, 1945. I’d first like to clarify the issue of whether he bears some form of responsibility for actually ordering the attacks, and whether his actions were wrong.

However, I think that the droppings of the A-bombs were actually decided during the time of Franklin Roosevelt. Therefore, an assessment of Roosevelt is necessary for this underlying issue. It would seem that he fundamentally created the direction for post-WWII American history and the new world order.

That should be effective, but as someone who likes to inspect history, I feel obliged to check whether America’s actions were “fair”.

Was the Last World War One Between “Gods” and “Demons”?

In the final count, Japan was defeated in the war, but was it a war between “gods” and “demons” as the West likes to portray? To put this gently, was it a battle between “democracy” and “fascism”? In other words, was it a conflict between “the West” and “the Fascist Axis of Japan, Germany, and Italy”?

It’s true to say that this is the approach often taken in the field of political science in the U.S., and people who have studied in the U.S. would probably have come across it. I don’t think anyone other then me has the ability to reveal the truth any more, but it does have tremendous, historical importance.

Master Okawa Summons the Spirit of the Former U.S. President Harry S. Truman.

I’ll try to invite Truman here.

At present, he’s the last U.S. president to have graduated from high school only. He must have been a very able man. He apparently had a long life, because he lived until the age of 88.

Oh, President Harry S. Truman, issuer of the order to drop the atomic bombs as 33rd President of the United States, please come down to the Hall of Great Awakening. Tell us the true significance of the war!

We’ve already investigated the Japanese side, and now I ask you to tell us about the American point of view and circumstances.

Oh spirit of Harry S. Truman, please come down to the Hall of Great Awakening, and tell us your opinions concerning the situation at the end of the war.

(A silence of about 20 seconds)

Truman Apologized, “They Shouldn’t Have Been Dropped.”

- Are you Harry Truman, the 33rd President of the United States?

Truman: (Sighs deeply) Ah…. What did I do? I did something unforgivable.

- What did you say just now?

Truman: You’re asking me about the A-bomb, aren’t you?

Truman: They should have never been used.

- You shouldn’t have dropped them? Did you realize that after you died?

Truman: Well, yes, I guess so. Mind you, I had a long life, and I gradually came to see it that way as the relationship between Japan and the U.S. improved after the war and we became friends.

During the war, I regarded Japan as a hateful enemy, and I was ready to use anything to defeat Japan. I lived a long life after the war, and when I returned to the Real World, I felt strongly that there might not have been any reason to use them after all.

As Soon As Atomic Bombs Came Into Existence, Japan Was the Target.

- Can you tell us the reason you ordered nuclear attacks when you were the American President?

Truman: Well, they’d been developed. Discussions about the actual use of the atomic weapons started even before the Japan-U.S. war began. In fact, ‘research’ got underway about 20 years before I dropped them, and I knew for a long time that scientists could theoretically develop them. When I was looking at how much longer it would take to complete them, the tests were finally successful.

I wanted to try the bombs in actual warfare, but of course, I couldn’t bear to use them in Europe since Germany and Italy were Christian countries like America.

Even though Hitler existed, it was still a Christian Protestant country. Therefore, I allowed the Soviet Union to invade, and we ultimately won the land war. I was unable to use the weapons there. In fact, they could have been dropped.

Berlin was practically in ruins from the air raids, but of course, it was easier to drop the bombs on Japan, which was not a Christian country. Maybe I should say that it was easier to win over public opinion for my decision.

- Chronologically speaking, Germany surrendered in May of 1945, and, to be precise, Trinity (mankind’s first nuclear test) was successfully staged in New Mexico on July 16th.

- It means the final A-bomb test was not completed before Germany’s surrender. For argument’s sake, would you have hesitated to use the A-bomb had Germany’s surrender been delayed?

Truman: I probably wouldn’t have used it. It wasn’t in the original plan, you see. The target was Japan right from the very start.

- Why was the bombing of Japan with a nuclear weapon your goal?

Truman: Because, after all, the American people couldn’t understand the Japanese. Before the war, many people were even calling for Japanese immigrants to be expelled.

As well as that, from the American point of view, that tiny country had entered Manchuria, occupied Mainland China, and invaded a succession of Asian countries that European countries had previously colonized. Japan had beaten Britain, France, and the Netherlands, and it was establishing a string of Japanese colonies. Well, as far as the people of America were concerned, despite the fact that my next remark might seem rather rude and insulting to the people of Japan, we felt as if there was no way we could let you Japs get away with it.

Truman Continues to Talk About the “Japanese Menace”.

- I believe that Japan didn’t attack civilians.

- However, America planned indiscriminate slaughters, such as the Great Tokyo Air Raid, right from the start, didn’t it? What were your opinions at the time?

Truman: It would be true to say that I regarded Japan as a totalitarian state. In terms of Japan, a totalitarian state meant that the Emperor alone was the “queen bee” or “queen ant”, and everyone else was in the same position as a “worker bee” or “soldier ant”. To me, all Japanese shared the same values, whether they were military or civilians. I regarded Japan as a kind of totalitarian state.

I Dropped Two A-bombs as an “Experiment”.

- Why did you use two bombs?

Truman: Well, it was to test two slightly different kinds of incendiaries.

Truman: Uh-huh. The Nagasaki and Hiroshima versions were slightly different types of the same bomb. We checked to see how much offensive power each of them had.

Truman Didn’t Want to Accept the Japanese as Being Equal Members of the Human Race

- There was that side of it, but even so, I can’t imagine that you could justify the slaughter of around 350,000 Japanese in two bombings. I wonder whether your racist views influenced your use of the nuclear weapons.

- You were aware that the Japanese were suing for peace after the Tojo government collapsed, weren’t you?

- How do you define a crime against humanity?

- What would you say is a crime against peace?

Truman: That’s what it would have been had I accepted the Japanese as being equal members of human race. During the war, I didn’t recognize the Japanese as being equivalent to other human beings the way that Caucasians were.

“The Nanking Massacre” Was Necessary to Balance “America’s Actions”.

- Class A war criminals are “guilty of killing many people”, aren’t they?

- The fabrication of the Nanking Massacre…

Truman: That was the hardest thing about the time when the war ended. America’s actions could have been labelled in a damaging way. We had to balance it out like that. We would have been in trouble unless the Japanese were seen as even more vicious than us.

America Boosted Its Fighting Spirit Through a Campaign to “Dehumanize the Japanese”.

- What do you think about the people who died in the atomic bombings? About the feelings of those who were burnt to death?

Truman: We aimed to boost our fighting spirit during the war. In America, we enthusiastically waged a campaign to convince people that the Japanese were inhuman.

The Democrats are a political party that emphasizes human rights, but there wasn’t the same doctrine of human rights as there is now. When it comes to American “human rights”, Lincoln said, “All men are created equal.” However, the word “men” referred white men it didn’t include blacks or women.

The liberation movements for blacks and women occurred in the 1960s, which was after I exploded the atomic bombs. From the perspective of those prejudicial times, it’d be true to admit that I didn’t see the Japanese in any regard as similar to us.

Was It Really Fascism Versus Democracy?

- It’s just that, looking back now, doesn’t it seem at least like there was a clear distinction along the lines of fascism and democracy?

Truman: We, Americans, created that idea to justify our actions.

There Is Some Truth in “the Greater East Asian War to Release European Karma”.

- Then, can you clearly state whether Japan’s war was right or wrong?

Truman: Um, I don’t know. If you say the Great Depression that started in the US caused it, I couldn’t say that I didn’t share some responsibility.

Japan certainly used the words “the Greater East Asian War” as an act to release the karma that Europe had accumulated in the centuries since the Age of Discovery, and I think in fact there’s some truth to it.

The Tokyo Trials, in Which “the Victorious Nations Judged the Defeated” Were Not Without Fear or Favor.

- Did the International Military Tribunal for the Far East really provide a fair trial? What was your opinion, Mr. Truman?

Truman: Well, it was obviously not fair, because the victors judged the losers. That’s why the United Nations itself isn’t neutral since the countries that won the war created the U.N. It’s an organization created to keep the losers permanently contained.

Truman: It’s an organization created after the war for the systems of the victorious nations to continue, and the U.N. isn’t even-handed.

Just as individuals have wants, as fellow citizens, we want to protect our own interests in order to maintain our advantage.

Thinking about it now, from the American point of view, I really didn’t want to include the Soviet Union and Communist China as permanent members in the Security Council. To be perfectly frank, it’s a bit of a shame they were as it would have been a much better set-up if they weren’t.

To be perfectly honest, if it were today, I would have wanted to include Japan and Germany instead of Russia and Communist China.

The Imposition of the Pacifist Constitution Was the Same As “the Subjugation of the Indians”.

- This is a question about the Japanese Constitution, and of course, the issue of Article 9.

- The Japanese Constitution was drafted in your day. And in that constitution Article 9 stipulates that the Japanese people forever renounce war and will not maintain war potential. What was your thinking on this issue at the time, Mr. Truman?

In addition, with the extension of China’s current hegemony, please give us your opinion on today’s international situation.

Truman: Well, it’s a really lousy constitution. America recognized its mistake when the Korean War started. America knew that it was a constitution that shouldn’t be imposed upon an independent country, and we abandoned it. However, the Japanese clung to it, you know.

It was awful matter, which we handled exactly in the same manner as the way we treated the Native Americans. We overcame them with our cavalry, and then we disarmed them. Article 9 should never have been imposed had we recognized Japan’s sanctity as a sovereign state.

- Are you saying that “war potential will never be maintained”, having been written into the Constitution, is in itself strange?

Truman: The Japanese have probably been brainwashed by it, haven’t they? Doesn’t it mean that they’ve vowed to be annihilated rather than to have an army and to kill foreign nationals? How do you interpret it?

- Mr. Truman, it’s no exaggeration to state that you decided the Japanese should be brainwashed.

Truman: Me… Was it me? Well, I don’t remember, but anyway, I only kept that opinion for five years. When the Korean War began, I already changed my mind. I did previously believe that Japan was a bad country. However, when I actually started interacting with the Japanese after the war, I saw first-hand that they were actually a rather advanced society and had long enjoyed a splendid culture. None of us in America knew that democracy had existed in pre-war Japan.

Truman: Americans didn’t really know about the Taisho period democracy or the greatness of the Meiji Restoration. We weren’t aware that Japan was a country with a history.

A Tearful Truman Utters Words of Self-Reflection.

- Well, this is my last question. Today, when politicians in Japan pay their respects at Yasukuni Shrine, other countries criticize them. What do you think about the people who fought in such wars?

Truman: They should pay their respects there. Hmm. Of course, they should. Nationality is not an issue in this business. Whatever enemies they fought against, they were people who didn’t fight out of self-interest they were people who fought to defend, and died for their country. It’s only natural that their successors should pray for them.

- There’s a way of looking at it in the media that says, “Class A war criminals have been enshrined there, and people mustn’t go and pay their respects”.

Truman: That’s wrong, isn’t it? I think that’s mistaken. If we’d been defeated, Americans would find it unforgivable if other countries were to tell them, “You mustn’t pay your respects.” From the perspective of human equality, people shouldn’t say that. I think they’re incorrect to comment on it.

Now, when I impartially look back on the military history of the world, I think that the Japanese army was truly excellent.

I’m sorry (suddenly bursting into tears).

The people of this tiny country with no natural resources really put up a brave fight… Excuse me. I really feel so sorry for them.

Even though they had no natural resources…I’d like you to ask Roosevelt about that. Anyway, they kept on fighting even though the oil, coal, and iron ore supplies had been cut off. I feel so sorry for them. Oh, they really put up a brave fight.

People must forgive the Japanese soldiers. They really tried hard. Oh, the poor things. I really feel so sorry for them. I have to reflect upon it now, I think. I’m sorry.

The president, who’s currently in office, probably can’t make an apology. As the person responsible for the atomic bombings, I must state that I would have probably started a war, too, had I been in Tojo’s position. I would have certainly waged war. Oh….. I am very sorry…

- President Truman, thank you very much for coming here today.

Master Okawa (to Truman): Thank you very much.

Ah…He seems to be suffering rather a lot, doesn’t he?

Master Okawa: He may almost never be able to forget that he’s the person who’s ultimately responsible for the atomic bombings.

- I think that’s the way of it.

Master Okawa: He might not be able to forget even after a thousand years because there are people who hate him, aren’t there?

Little Boy: The First Atomic Bomb

Two American atomic bombs ended World War II in August 1945, and the devastation will be forever remembered. In an instant when the first bomb was dropped, tens of thousands of residents of Hiroshima, Japan were killed by “Little Boy,” the code name for the first atomic bomb used in warfare in world history.

Hiroshima after atomic bombing, 1946. (National Archives Identifier 148728174)

The Project

Scientists developed the technology for the atomic weapon during the highly classified project code-named “The Manhattan Project.” U.S. Army Col. Leslie R. Groves oversaw the military’s participation, while civilian scientist Robert Oppenheimer was in charge of the team designing the core details of Little Boy. Facilities for the research were set up in Manhattan, Washington State, Tennessee, and New Mexico. Scientists on the project drew from the earlier work done by physicists Enrico Fermi and Leo Szilard, both of whom received funding from the U.S. Government in the late 1930s to study enriched uranium in nuclear chain reactions. The enriched uranium-235 was the critical element in creating an explosive fission reaction in nuclear bombs.

The Manhattan Project team agreed on two distinct designs for the atomic bombs. In Little Boy, the first atomic weapon, the fission reaction occurred when two masses of uranium collided together using a gun-type device to form a critical mass that initiated the reaction. In effect, one slug of uranium hit another after firing through a smooth-bore gun barrel. The target was in the shape of a solid spike measuring seven inches long and four inches in diameter. The cylinder fit precisely over the spike as the two collided together creating the highly explosive fission reaction. While the theory of the gun firing concept was not fully tested until the actual bomb dropped on Hiroshima, scientists conducted successful lab tests on a smaller scale that gave them confidence the method would be successful.

The final construction of Little Boy occurred in stages. Various components of the bomb were transported by train from Los Alamos, New Mexico, to San Francisco, California. There, the heavy cruiser USS Indianapolis shipped the collection of parts to Tinian Island in the Pacific Ocean south of Japan, where it arrived on July 26. In order to prevent a catastrophic accident, the target piece of enriched uranium flew separately aboard three C-54 Skymaster transport planes to Tinian Island, where it also arrived on July 26. Upon final assembly, Little Boy weighed 9,700 pounds and measured 10 feet in length and 28 inches in diameter.

Atomic bomb preparations at Tinian Island, 1945. (National Archives Identifier 76048771)

Once on Tinian, the officer in charge of Little Boy’s assembly, U.S. Navy Capt. William S. Parsons, decided to forestall the final segment of assembly until the very last moment. He did this in order to prevent a catastrophic accidental detonation caused by an electrical short or crash.

The Mission

In the early morning hours of August 6, 1945, a B-29 bomber named Enola Gay took off from Tinian and proceeded north by northwest toward Japan. The bomber’s primary target was the city of Hiroshima, located on the deltas of southwestern Honshu Island facing the Inland Sea. Hiroshima had a civilian population of almost 300,000 and was a critical military center that included 43,000 soldiers.

Topographical map, Hiroshima. (National Archives Identifier 166126365)

The aircraft, piloted by the commander of the 509th Composite Group, Col. Paul Tibbets, flew at low altitude on automatic pilot before climbing to 31,000 feet as it closed in on the target area. At approximately 8:15 a.m. Hiroshima time, the Enola Gay released “Little Boy” over the city. Forty-three seconds later, a massive explosion lit the morning sky as the bomb detonated 1,900 feet above the city, directly over a parade field where soldiers of the Japanese Second Army were doing calisthenics.

Even though the Enola Gay had already flown 11 and a half miles away from the target after dropping its payload, it was rocked by the blast. After the initial shock wave hit the plane, the crew looked back at Hiroshima, and Tibbets recalled that “The city was hidden by that awful cloud . . . boiling up, mushrooming, terrible and incredibly tall.” [1] The force of the explosion was later estimated at 15 kilotons (the equivalent of 15,000 tons of TNT).

Col. Paul W. Tibbets, Jr., pilot of the Enola Gay, waves from the cockpit before takeoff, August 6, 1945. (National Archives Identifier 535737)

Many Americans viewed the bombing as a necessary means toward an end to the conflict with Japan. When Dr. J. Robert Oppenheimer was briefed on the bombing, he expressed guarded satisfaction. He, more than any other, understood the power of the weapon he helped produce and the destruction that was unleashed on humanity.

Enola Gay returns after strike at Hiroshima, 1945. (National Archives Identifier 76048622)

We will never definitively know how many died as a result of the bombing of Hiroshima. Some 70,000 people are estimated to have perished as a result of the initial blast, heat, and radiation effects. This included about 20 American airmen who were held as prisoners in the city. By the end of 1945, because of the continuing effects of radioactive fallout and other after effects, including radiation poisoning, the Hiroshima death toll was likely over 100,000. The five-year death total may have even exceeded 200,000, as cancer and other long-term effects are considered.

Read the blog post Harry Truman and the Bomb and the notes of Captain Robert Lewis, co-pilot of the Enola Gay, to learn more about the first atomic aomb.

Hiroshima: Before and After the Atomic Bombing

Later this month, Barack Obama will become the first U.S. president to visit Hiroshima, Japan, 71 years after the United States dropped the first atomic weapon used in warfare on the city in 1945, killing tens of thousands. President Obama plans to tour the site with Japan's Prime Minister Shinzo Abe, but will reportedly not be offering any apologies or revisiting the decision by the U.S. to drop the bomb. On my last visit to the National Archives, I found a number of pre-war and post-war images of Hiroshima, and have gathered them here, a stark reminder of what happened when a nuclear weapon was detonated over a densely-populated area.

A pre-war photograph of Hiroshima’s vibrant downtown shopping district near the center of town, facing east. Only rubble and a few utility poles remained after the nuclear explosion and resultant fires. #

Looking upstream on the Motoyasugawa, toward the Product Exhibition Hall building (dome) in Hiroshima, before the bombing. The domed building was almost directly below the detonation, which occurred in mid-air, about 2,000 feet (600 meters) above this spot. Today, much of the building remains standing, and is known as the Atomic Bomb Dome, or the Hiroshima Peace Memorial. #

Looking northeast along Teramachi, the Street of Temples, in pre-war Hiroshima. This district was completely ruined. #

Looking north from the vicinity of the Aioi Bridge (the central T-shaped bridge targeted by the bomb). Wooden houses line the bank of the Otagawa, with traditional Japanese river boats in the foreground. #

Aerial view of the densely built-up area of Hiroshima along the Motoyasugawa, looking upstream. Except for the very heavy masonry structures, the entire area was devastated. Ground zero of the atomic bomb was upper right in the photo. #

Hiroshima Station, between 1912 and 1945. #

A pre-war photo of Ujina Harbor. This relatively small harbor was developed as the port for Hiroshima and was one of the principal embarkation depots for the Japanese Army during World War II. #

On August 6, 1945, a mushroom cloud billows into the sky about one hour after an atomic bomb was dropped by American B-29 bomber, the Enola Gay, detonating above Hiroshima, Japan. Nearly 80,000 people are believed to have been killed immediately, with possibly another 60,000 survivors dying of injuries and radiation exposure by 1950. #

Survivors of the first atomic bomb ever used in warfare await emergency medical treatment in Hiroshima, Japan, on August 6, 1945. #

Shortly after the atomic bomb was dropped over the Japanese city of Hiroshima, survivors receive emergency treatment from military medics on August 6, 1945. #

Civilians gather in front of the ruined Hiroshima Station, months after the bombing. #

Japanese troops rest in the Hiroshima railway station after the atomic bomb explosion. #

Streetcars, bicyclists, and pedestrians make their way through the wreckage of Hiroshima. #

One of several Japanese fire engines transferred to Hiroshima shortly after the bombing. #

Hiroshima after the bombing. #

A Japanese woman and her child, casualties in the atomic bombing of Hiroshima, lie on a blanket on the floor of a damaged bank building converted into a hospital and located near the center of the devastated town, on October 6, 1945. #

The devastated landscape of Hiroshima, months after the bombing. #

𠇍irection of blast” chalk marks and outlines of the feet of a victim caught in the explosion. The intense heat of the initial flash of the detonation seared every nearby surface, leaving inverted “shadows,” like those seen on this bridge left by the railings and by a person who had been standing in this place. #

Post office savings bank, Hiroshima. Shadow of window frame left on fiberboard walls made by the flash of the detonation. October 4, 1945. #

In Hiroshima, gas tanks showing shadowing effects of the flash on asphalt paint. #

Two Japanese men sit in a makeshift office set up in a ruined building in Hiroshima. #

The shattered Nagarekawa Methodist Church stands amid the ruins of Hiroshima. #

A huge expanse of ruins left after the explosion of the atomic bomb in Hiroshima. #

An aerial view of Hiroshima, some time after the atom bomb was dropped on this Japanese city. Compare this with pre-war photo number 5 above. #

A Japanese soldier walks through a completely leveled area of Hiroshima in September 1945. #

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