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Wednesday, May 11, 2005

Atomic Bomb Section 3 The decision to drop the bomb / How the cities were chosen / Why there was no demonstration bombing

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Section 3 The decision to drop the bomb / How the cities were chosen / Why there was no demonstration bombing

The decision to drop the atomic bomb had to have been one of the most difficult decisions anyone has ever made. It opened a new era of warfare with destruction on a scale that had never been seen before. To think that one airplane, with one bomb, could destroy an entire city was the stuff of science fiction. In fact, to most, it was incomprehensible. There was just no way to imagine the destructive power of the atom bomb.

As we look into the decision to drop the bomb, we need to look into charges that have been leveled against President Truman and the United States. Detractors like to say that dropping the bomb was racially motivated. Others like to say it was dropped as an example to Stalin of our power. Others say that it was politically motivated, meaning that they had spent over $2 billion developing it, they had damn we better use it.

Looking at historical records, you can always find someone, who said something at some certain time that will corroborate your pet theory. There were thousands of people working on the project and so you will cover just about every type of person there is. The important thing to look at is the man who made the decision, President Harry Truman. President Truman was a decent, honest and considerate person. He was probably one of the most honest and candid presidents in the past 100 years. When you read biographies of him, none of the major biographers find him to be mendacious; nor do they think racism or anti-Stalinist motives swayed his decision. President Truman was a man of character and to put his decision to use the bomb down to racism or that it was politically motivated does this great man a huge disservice.

When making the decision of whether or not to drop the bomb, there were various factors in play. The first and foremost being, will dropping the bomb shorten the war and allow for less Allied casualties. Will dropping the bomb force Japan to surrender? And will the surrender under the terms we give?

The next decision to be made was just how to use the bomb. Would it be dropped on a city? Would it be used in a demonstration? Or, will we let the world know we have it and not use it? All of these things were considered and the consideration began early on.

In May 1943, members of the Manhattan project realized that they would most likely not have the bomb ready before the end of the war in Europe, but would likely have it ready for the fight against Japan. Even back then, they tried to decide where the best place to drop the bomb would be and thought that the Japanese naval station at Truk would be an ideal target.

President Roosevelt also had this on his mind, when meeting with Churchill in 1944 they discussed how the first bomb should be used. They concluded that it would best be used somewhere in Japan and then warn the Japanese that more would be dropped until they surrendered. Still, Roosevelt continued to consider the problem of how to use the bomb. He discussed this with others wondering if it should just be held as a threat or that maybe a demonstration of its power in an uninhabited area might be sufficient.

The discussion of how to use the bomb was also taking place among the scientists that were building it. Secretary of War Stimson and General Marshall were concerned as well and organized a committee called the, “Interim Committee” to study this issue. This was a powerful group consisting of Assistant Secretary of War George Harrison, Vannevar Bush, Karl Compton of MIT, Under Secretary of the Navy Ralph Bard, Assistant Secretary of State William L. Clayton and Secretary of State James Byrnes. This august group was advised by Arthur Compton, Ernst Lawrence, Robert Oppenheimer and Enrico Fermi.

The scientific community was of a mixed mind on how to use the bomb. They understood best just how destructive of a weapon they were building. They also understood that these first bombs were relatively weak compared to what would soon be produced. They felt that atomic power must be controlled and controlled quickly. For the most part, they were looking at the long term effects of atomic weapons and not what was currently of concern to the rest of the country. Most, not all were against its use. They felt that if the bomb was dropped, it would alienate the US from the rest of the world and that it would make it difficult to call for the control of atomic power. Some favored a demonstration of the bombs potential with leaders from all the great nations of the world being invited to watch.

Some of the scientists decided to act on their fears. Leo Szilard, one of the scientists who convinced Roosevelt to pursue the project, felt very strongly that if we used the atom bomb against Japan, it would force Russia to push even harder to produce their own atomic weapon. Szilard and some of those that agreed with him tried to meet with President Roosevelt to discuss the issue. When that failed, they tried to meet with Mrs. Roosevelt. A meeting was scheduled, but then cancelled with her husband’s death.

This didn’t stop the scientists. They tried to arrange to meet with Truman. Instead, they were allowed to meet with James Byrnes. The meeting did not go well at all and the influence of these scientists was greatly diminished afterwards. Basically, their own arrogance was their downfall. In the memo they prepared for Byrnes, it read in part:

Thus the Government of the Untied States is at present faced with the necessity of arriving at decisions which will control the course that is to be followed from her on: These decisions ought to be based not on the present evidence relating to atomic bombs, but rather on the situation which can be expected to confront us in this respect a few years from now. This situation can be evaluated only by men who have first-hand knowledge of the facts involved, that is, by the small group of scientists who are actively engaged in this work. This group includes a number of eminent scientists who are willing to present their views, that is, however, no mechanism through which direct contact would be maintained between them and those men who are, by virtue of their position, responsible for formulating the policy which the United States might persue.

Neither the scientists nor Byrnes felt the meeting went well and Byrnes had no desire to work with this group of men.

During this time, Marshall too had been thinking about how to use the bomb. He told Stimson the weapon should first be used on, “straight military objectives such as a large naval installation.” Then, if this didn’t bring about their surrender they could be used on, “large manufacturing areas from which people would be warned to leave—telling the Japanese that we intend to destroy such centers.” He felt that a warning was extremely important to keep our moral standing. “Every effort should be made to keep our record of warning clear. We must offset by such warning methods the opprobrium which might follow from an ill-considered employment of such force.”

A short time after this, the powerful Interim Committee held an all day meeting, May 31, to discuss all the issues that related to the bomb. One of the major issues discussed was providing a demonstration of the atomic bomb. They discussed many questions, problems and concerns with having a demonstration bombing. Where would the demonstration be held? Would you have it in neutral territory with observers from countries around the world? How long would it take to make preparations to do a demonstration like this? What if it didn’t work, what if the bomb was a dud? That would be an incomprehensible disaster. Is there any reason to think that such a demonstration would be enough to convince the military leaders of Japan to surrender? Also, since Japan’s military controlled the press, would the people of Japan ever hear of it?

Other considerations were discussed as well. If the demonstration were high over a Japanese city where it could be seen with little damage done, would it be convincing? It was finally concluded that no matter where a demonstration was held, it would do little to impress the Japanese enough to surrender. They then discussed warning the Japanese before dropping a bomb over a city where the destruction could be measured. This too was shot down. Warning the Japanese would give them time to marshal their defenses, send up their fighters or even move POWs into the city. Again, if there was a warning and the bomb was a dud, it would embolden the Japanese even more.

The scientists involved were still concerned. They didn’t feel that their concerns were getting a fair hearing. They formed six committees to deal with future research, social and political implications of the bomb, educating the public about atomic energy, production, control and organization. The most important of these was the Social and Political Implications committee which was chaired by James Franck. The submitted a report which became known as the “Franck Report.”

The “Franck Report” covered a variety of topics. They felt that there was a great concern for the future and that the United States would be in great danger if there was a proliferation in atomic weapons. They felt that too many other nations knew of the basics of atomic weapons and that the US could never maintain a lead. They also felt that in the next war, a first strike would be the most likely approach and that would leave the US vulnerable. They felt that international control or agreements covering all use and manufacture of atomic weapons were essential for world safety.

The report continues on denouncing the use of the atomic bomb on Japan. The approach is much different than others though as they feel that the bomb, in its current form, is not powerful enough to make a difference. While the bomb might be able to level a city, it is no more than the current bombing had already been doing. They again argue for a test on a desert island first, then, if Japan does not surrender, using it on a city feeling that it would be on the heads of the leaders of Japan for what happened.

Not all the scientists agreed and reports from other committees varied on their recommendations. Robert S. Stone, the director of the health division, wrote the following:

The fact that we have developed this weapon without the knowledge of our allies other than the British convinces me that there will be a certain element of mistrust amongst the other allies no matter how we introduce it. Moreover, it is inconceivable to me that the French and Russians are not already well aware of the possibilities even though they may not be as far along in the practical development as we are. Under these circumstances I feel that we would be losing nothing by using the weapon in our war against the Japanese. Any respect which the Russians have for us will not be increased if they later find that we had a valuable weapon which we did not use… I feel quite strongly that we will be in a better position to secure international agreement on its suppression after its effectiveness has been demonstrated.

Comparing this to the “Franck Report” we can see that there was no real agreement even among the scientists on how we should proceed.

Finally, the scientists who were advising the Interim Committee met. While they didn’t keep notes, Arthur Compton wrote the following about their meeting:

Ten days later, at Oppenheimer’s invitation, Lawrence, Fermi and I spent a long weekend at Los Alamos… We were determined to find, if we could, some effective way of demonstrating the power of an atomic bomb without loss of life that would impress Japan’s warlords. If only this could be done! Ernest Lawrence was the last one of our group to give up hope for finding such a solution. The difficulties of making a purely technical demonstration that would carry its impact effectively into Japan’s controlling councils were indeed great. We had to count on every possible effort to distort even obvious facts. Experience with the determination of Japan’s fighting men made it evident that the war would not be stopped unless these men themselves were convinced of the futility.

While it was difficult for them, even this group finally decided that the bomb should be used by the military. Finally this group gave their report, agreed upon unanimously, to the Committee.

In their report, they had several recommendations. First, that the bomb should be discussed with the other Allies before using it. They also said that as scientists, they had no special competence for solving political, social and military problems as to dealing with atomic power. This went along with what was the second point of their report:

(2) The opinions of our scientific colleagues are not unanimous; they range from the proposal of a purely technical demonstration to that of the military application best designed to induce surrender. Those who advocate a purely technical demonstration would wish to outlaw the use of atomic weapons… Others emphasize the opportunity of saving American lives by immediate military use… We find ourselves closer to these latter views; we can propose no technical demonstration likely to bring an end to the war; we see no acceptable alternative to direct military use.

Oppenheimer later wrote, “We did say that we did not think exploding one of these things as a firecracker over a desert was likely to be very impressive… The destruction in the desert is zero…” Even Szilard, who was the most outspoken in his opposition to using the bomb, later wrote, “I think it is clear that you can’t demonstrate a bomb on an uninhabited island. You have to demolish a city.”

The Interim Committee gave the idea of a demonstration its full and undivided attention. They looked at it from every conceivable angle and in the end, determined that it just wasn’t feasible. There were too many things that could go wrong and no way of guaranteeing that it would make the necessary impact on Japanese leaders. It was determined that only by the destruction of heretofore untouched city, would the full power of the atomic bomb be seen, calculated and felt. It was only by destroying an entire city with one bomb could they shock the Japanese government into an early surrender.

Dr. Mitchell Wilson was asked to work on the Manhattan Project. Dr. Wilson refused on moral grounds, not wanting anything to do with an atomic weapon. Later in his life, in 1960, he was sent around the world on an investigation of different styles in science. One of the countries he went to was Japan. He writes:

There are those who have become absolutely certain that the bombing of Hiroshima was a mistake. Not until I went to Japan did I realize that all the discussions I had heard had been among Western scientists only, thinking in Western terms, and taking for granted that the Japanese High Command would necessarily have reasoned along similar lines. In Tokyo, I discussed the question at last with a number of Japanese scientists who were old enough to have lived through the times. When I asked these men to describe for me what sort of demonstration of the atomic bomb by the United States in the summer of 1945 would have convinced the Japanese High Command of the inevitability of defeat and the need for immediate surrender, I drew a blank stare at the total unreality of the question in the light of the situation as it then existed.

Wilson later discussed this saying, “Whatever verdict history will pass on the need to destroy Hiroshima and Nagasaki… when the matter is put in terms of the Japanese values generally accepted during the war, Japanese scientists themselves can suggest no realistic alternative to what happened. That there might have been a premilitary demonstration of the atom bomb turns out to be another one of history’s myths.”

Now that the decision was made to drop the bomb, Marshall decided to turn the targeting over to a committee made up of the Manhattan Project leaders. He felt that because of the technical considerations and security risks, targeting couldn’t be left up to theatre commanders like other bombing missions were. The target committee met in April and in May. There were two major considerations that focused their discussions, one, there would be few bombs so two, there would be few targets. It was decided that the targets chosen should be places that would most adversely affect the will of the Japanese people to continue the war. Beyond that, they should be military in nature, with either important headquarters, troop concentrations, centers of production of military equipment or supplies. Also, so that they could accurately study the effects of the bomb, it should be a place that had not been previously attacked. They also wanted the first targets to be large enough to contain the entire amount of damage so they could determine just how powerful the bomb was.

During the first meeting of the committee it was decided that the first bomb needed to be dropped under visual conditions to ensure there were no aiming errors. They also wanted to drop it on a clear day. They decided that it needed to be an urban area, not less than three miles in diameter in a large, populated area. That would help ensure they could accurately calculate the power of the bomb.

When the committee met again, they discussed what they hoped would be the power of the bombs. “Little Boy,” the uranium bomb, was hoped to be the equivalent of between 5,000 to 15,000 tons of TNT. “Fat Man,” the plutonium bomb, was considered a crap shoot, somewhere between 700 and 5000 tons of TNT. They also decided that a purely military target would not have the psychological impact necessary to force a surrender so the target needed to be a compromise of military and urban. They also wanted it to be significant enough to receive world wide attention and publicity.

With these things in mind, a list of cities was made. Kyoto, Hiroshima, and Yokohama and the Kokura arsenal were chosen. Niigata was put on the list as an alternative. Kyoto headed the list because of its large size, the fact that it was untouched to this point and its cultural importance. The committee felt that it would cause a huge blow to the Japanese psyche to lose Kyoto. Finally, on their third meeting, they reduced the list to three, Kyoto, Hiroshima and Niigata. They decided to aim at the center of the city and not a specific industrial area, because the bomb might “miss” the intended point of impact by up to a fifth of a mile. If it missed, they still wanted it to be close enough so that they would be able to at least measure the power of the bomb.

While the targeting committee was making its decisions, Stimson decided to involve the Interim Committee on the targeting issue as well. Minutes from their first meeting included the following:

After much discussion concerning the various types of targets and effects to be produced, the Secretary expressed the conclusion, on which there was general agreement, that we could not give the Japanese any warning, that we could not concentrate on a civilian area, but that we should seek to make a profound psychological impression on as many Japanese as possible. At the suggestion of Dr. Conant the Secretary agreed that the most desirable target would be a vital plant employing a large number of workers and closely surrounded by workers’ houses.

This recommendation was passed on to President Truman who concurred with it.

This is an indication of how bombing had progressed, or digressed if you rather. From early on, when they tried to confine bombing to purely military targets, it slowly changed to include entire cities. The firebombings of cities killed hundreds of thousands. It isn’t hard to see how the use of the first atom bombs was not relegated to purely military targets. No country was immune to this, all the major powers in World War II performed indiscriminate bombing on major urban areas. It became part of the war, part of normal warfare, at least for a time. Still, reading the notes and minutes of meetings as well as journal entries, you get a sense that it bothered all those involved. Even when planning to bomb a major city, they tried to justify it by looking for a close military target.

Finally, the job of dropping the bomb was given to the 509 Composite Group. They had been training to drop the bomb, running test runs around the cities that had been designated targets. On July 25th, orders were received to drop the “first special bomb” after August 3rd, weather permitting. The targets were listed in the orders in sequential order, Hiroshima, Kokura, Niigata and Nagasaki. Kyoto was no longer on the list.

Kyoto was off the list and Nagasaki had been added. Secretary Stimson, on his own authority, deleted the name. Stimson had visited Japan many times before the war and was enamored with the history and culture he found in Kyoto. Despite the urging of those under him to leave it on the list, he decided the cultural relics found there were too important to destroy. The addition of Nagasaki on the list infuriated Spaatz and Nimitz who both sent messages reminding those above them of the prisoner-of-war camp that was in Nagasaki.

Hiroshima was the largest city outside of Kyoto to remain undamaged. Its population in 1940 was 344,000 and the city was known as an army city. It could legitimately be considered a military target. Hiroshima contained the headquarters of the Fifth Division and was a primary port of embarkation. The military report on the city said:

The entire northeast and eastern sides of the city are military zones. Prominent in the north central part of the city are the Army Division headquarters marked by the Hiroshima Castle, numerous barracks, administrative building and ordnance storage houses. In addition, there are the following military targets: Army Reception Center, large Military Airport, Army Ordnance Depot, Army Clothing Depot, Army Food Depot, large port and dock area, sever shipyards and ship building companies, the Japan Steel company railroad marshalling yards and numerous aircraft component parts factories…

The city was also considered large enough to contain the damage caused by the blast. Outside of the official report, it was known to American intelligence that the city housed the headquarters of Field Marshal Hata’s Second General Army and 43,000 soldiers. This gave Hiroshima the highest density of servicemen to civilians among Japan’s large urban areas.

At 2:45 AM on August 6, 1945 the Enola Gay began its takeoff roll. It was followed by 2 planes carrying scientific instruments. 3 weather planes had taken off earlier to scout the target area and make sure all was ready. Little Boy detonated at 8:16 AM after a 43 second fall to an altitude of 1,900 feet over the courtyard of the Shima Hospital. It was 550 feet southeast of its aiming point, the Aioi Bridge. The bomb was calculated to be equivalent of 12,500 tons of TNT. It created a blinding flash that lasted 1/10 of a second and reached 5,400 degrees Fahrenheit.

On August 9, 1945, Bock’s Car took off carrying Fat Man headed for Kokura. Because of poor weather conditions over Kokura, they were unable to drop the bomb. They headed for their secondary target, Nagasaki. Nagasaki had a 1940 population of 253,000 and was the third largest city on the island of Kyushu. It contained the Mitsubishi shipyard, the largest and most productive in Japan. Even though the weather was bad and against orders, Frederick Ashworth, the bomb commander, decided to make a radar guided run. Fat Man missed its target by over a mile and detonated over the Misubishi torpedo factory and the Urakami Catholic Cathedral. Because of where it landed, it did far less damage than Little Boy had done despite the fact that it was estimated to have been the equivalent of 22,000 tons of TNT. The death toll from both bombs is estimated at between 100,000 and 200,000 dead.

President Truman made a difficult decision. He received advice from the best and brightest of the day. Military leaders, politicians, advisors and scientists all gave their best advice according to their knowledge, hearts and beliefs. Their main concern was saving lives and ending the war. It wasn’t easy, no matter what decision was made, thousands would die. The hard decisions were made, the bombs were dropped and the war ended.

Section 4 Why did this have to happen, wasn’t Japan Trying to Surrender?