"Above all, it should be appreciated that we are faced only with the beginning of a development and that, probably within the very near future, means will be found to simplify the methods of production of the active substances and intensify their effects to an extent which may permit any nation possessing great industrial resources to command powers of destruction surpassing all previous imagination. Open Letter to the United Nations by Niels Bohr

As the rapid advancement of technology and industry continued throughout the 20th century, so did the destructive capabilities of nuclear weapons, such as the development of hydrogen bombs.

A hydrogen bomb uses the heat generated by an atomic bomb, to perform nuclear fusion — which is when the nuclei of an atom, in this case, a Hydrogen nuclei, fuses together with other nuclei to form a new element, in this case, a Helium nuclei.

For a more in-depth look at hydrogen fusion, look at this annotation!

How strong is a hydrogen bomb?

A hydrogen bomb is a thousand times more powerful than an atomic bomb. The bomb dropped on Hiroshima which killed 140,000 people had the power of 13 kilotons; a hydrogen bomb has the power of 10 megatons. All the explosions that occurred throughout World War II combined to only two megatons — 20% of a hydrogen bomb’s total power.

Here is an interesting article comparing an atom bomb and a hydrogen bomb!

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The secrecy regarding the project which prevented public knowledge and open discussion of a matter so profoundly affecting international affairs added, of course, to the complexity of the task of the statesmen. With full appreciation of the extraordinary character of the decisions which the proposed initiative involved, it still appeared to me that great opportunities would be lost unless the problems raised by the atomic development were incorporated into the plans of the allied nations for the post-war world. Open Letter to the United Nations by Niels Bohr

The secrecy of the aforementioned Manhattan Project was one of the problems standing in the way of reaching an agreement betwwen nations on the matter. The full knowledge of the project was known by very few such as President Roosevelt and Churchill; Vice-President Truman didn’t even know the Manhattan Project existed until he became President!

The Soviet Union’s leader, Joseph Stalin, despite being allies with the United States and Great Britain during World War II, weren’t even told about the project. When the Soviet leaders discovered the United State’s plans for an atomic bomb, a great amount of distrust formed between the United States and the Soviet Union — thus making it harder for the two nations to cooperate together on the matter.

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The prevention of a competition prepared in secrecy will therefore demand such concessions regarding exchange of information and openness about industrial efforts including military preparations as would hardly be conceivable unless at the same time all partners were assured of a compensating guarantee of common security against dangers of unprecedented acuteness. Open Letter to the United Nations by Niels Bohr

Bohr and many other scientists working on the atomic bomb project suspected that the only way for countries to give up their supply and developmental plans involving atomic bombs would be if everyone benefited from the acquisition. This is where the United Nations came into play. If the United Nations controlled the atomic bomb supply, the bombs would be in neutral hands; therefore, the power of the bombs wouldn’t be abused and will ensure global safety for everyone.

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The present moment where almost all nations are entangled in a deadly struggle for freedom and humanity might at first sight seem most unsuited for any committing arrangement concerning the project. Not only have the aggressive powers still great military strength, although their original plans of world domination have been frustrated and it seems certain that they must ultimately surrender, but even when this happens, the nations united against aggression may face grave causes of disagreement due to conflicting attitudes towards social and economic problems. Open Letter to the United Nations by Niels Bohr

The aggressive powers Niels is referring to is the Axis Powers. The three major Axis Powers were Nazi Germany, Fascist Italy, and the Japanese. The goal of the Axis Powers was to form empires in Europe and Asia, which they nearly accomplished.

The combatants of the Axis Powers were known as The Allies The three major powers in The Allies were the United States, British Commonwealth, and the Soviet Union. The goal of the Allies was to stop the expansion of the Axis Powers, which they would accomplish. Even though the United States and the Soviet Union were allies during this war, they still had a disliking for each other, they just had a much bigger enemy in Germany; this is why they were enemies throughout the Cold War.

Remember that Niels is quoting a previous message sent to President Roosevelt before the war ended.

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"It certainly surpasses the imagination of anyone to survey the consequences of the project in years to come, where in the long run the enormous energy sources which will be available may be expected to revolutionize industry and transport. The fact of immediate preponderance is, however, that a weapon of an unparalleled power is being created which will completely change all future conditions of warfare. Open Letter to the United Nations by Niels Bohr

Niels prediction that using atomic energy for nuclear power will become significant in industry is correct.

Today, nuclear power accounts for nearly 1/5th of the United States electricity; there is 100 operating nuclear power plants spread out over 31 different states.

In 2012, nuclear power generated the largest percentage of electricity in seven states:

  • State Percent
  • Vermont 74.4
  • South Carolina 53.0
  • New Jersey 51.7
  • Illinois 48.8
  • Connecticut 47.8
  • New Hampshire 42.5
  • Virginia 40.5

Also, nuclear power provided 12% of the world’s electricity production in 2011. There are thirteen countries world-wide that produce at least one-quarter of their total electricity through nuclear power.

Read more about nuclear power production here and here.

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Everyone associated with the atomic energy project was, of course, conscious of the serious problems which would confront humanity once the enterprise was accomplished. Quite apart from the role atomic weapons might come to play in the war, it was clear that permanent grave dangers to world security would ensue unless measures to prevent abuse of the new formidable means of destruction could be universally agreed upon and carried out.

As regards this crucial problem, it appeared to me that the very necessity of a concerted effort to forestall such ominous threats to civilization would offer quite unique opportunities to bridge international divergences. Above all, early consultations between the nations allied in the war about the best ways jointly to obtain future security might contribute decisively to that atmosphere of mutual confidence which would be essential for co-operation on the many other matters of common concern.
Open Letter to the United Nations by Niels Bohr

After the war ended, the United States formed the United States Atomic Energy Commission. This agency’s purpose was to control the development and research of atomic energy after the war. Furthermore, the McMahon/Atomic Energy Act of 1946 transferred control of atomic energy research from the military to the people.

Despite there being some form of regulation on atomic energy in the United States, there was little to none on an international level at this time. There were several calls for action, such as Bohr’s, to put American nuclear arms under international control in order to prevent an arms race and prevent any further use of atomic bombs, but these proposals would never make it through due to the United Nations and the Soviet Union not reaching mutual terms.

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The fear of being left behind was a strong incentive in various countries to explore, in secrecy, the possibilities of using such energy sources for military purposes. The joint American-British project remained unknown to me until, after my escape from occupied Denmark in the autumn of 1943, I came to England at the invitation of the British government. At that time I was taken into confidence about the great enterprise which had already then reached an advanced stage. Open Letter to the United Nations by Niels Bohr

The Manhattan Project was kept a major secret from the public eye in hopes of preventing the Axis Powers from finding out that they were developing atomic bombs, too. It is estimated that a very small portion out of the 100,000+ that worked actually knew what they were working on.

A manager after the war said this in an interview:

Well it wasn’t that the job was tough… it was confusing. You see, no one knew what was being made in Oak Ridge, not even me, and a lot of the people thought they were wasting their time here. It was up to me to explain to the dissatisfied workers that they were doing a very important job. When they asked me what, I‘d have to tell them it was a secret. But I almost went crazy myself trying to figure out what was going on

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For the modern rapid development of science and in particular for the adventurous exploration of the properties and structure of the atom, international co-operation of an unprecedented extension and intensity has been of decisive importance. The fruitfulness of the exchange of experiences and ideas between scientists from all parts of the world was a great source of encouragement to every participant and strengthened the hope that an ever closer contact between nations would enable them to work together on the progress of civilization in all its aspects.

Yet, no one confronted with the divergent cultural traditions and social organization of the various countries could fail to be deeply impressed by the difficulties in finding a common approach to many human problems. The growing tension preceding the second world war accentuated these difficulties and created many barriers to free intercourse between nations. Nevertheless, international scientific co-operation continued as a decisive factor in the development which, shortly before the outbreak of the war, raised the prospect of releasing atomic energy on a vast scale.
Open Letter to the United Nations by Niels Bohr

At the time of Bohr’s writing of this letter, there were multiple new discoveries about atoms from scientists all over the world since the beginning of the 20th century despite there being troubled relationships between nations, limiting cooperation, especially the years before World War II. Some of these discoveries include:

  • The introduction of the Rutherford Model — which explained that the majority of the mass and the protons were located in the nucleus of the atom.

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My association with the American-British atomic energy project during the war gave me the opportunity of submitting to the governments concerned views regarding the hopes and the dangers which the accomplishment of the project might imply as to the mutual relations between nations. While possibilities still existed of immediate results of the negotiations within the United Nations on an arrangement of the use of atomic energy guaranteeing common security, I have been reluctant in taking part in the public debate on this question. In the present critical situation, however, I have felt that an account of my views and experiences may perhaps contribute to renewed discussion about these matters so deeply influencing international relationship.

In presenting here views which on an early stage impressed themselves on a scientist who had the opportunity to follow developments on close hand I am acting entirely on my own responsibility and without consultation with the government of any country. The aim of the present account and considerations is to point to the unique opportunities for furthering understanding and co-operation between nations which have been created by the revolution of human resources brought about by the advance of science, and to stress that despite previous disappointments these opportunities still remain and that all hopes and all efforts must be centered on their realization.
Open Letter to the United Nations by Niels Bohr

This American-British atomic energy project Niels is talking about is now known as the Manhattan Project. The Manhattan Project started in the middle of World War II, and the goal of the project was to figure out how to take atomic energy, and use it to make a bomb. The project was kept a secret, and the research cities were spread out through the United States and Canada.

The destruction the atomic bombs did to Hiroshima and Nagasaki made many scientists, such as Bohr and others who worked on the Manhattan Project, wary of the use of atomic bombs for warfare. Immediately after World War II, many countries started to develop and test their own atomic bombs; the development of atomic bombs in rival countries, predominately the United States and the Soviet Union, led to the start of the Cold War. Even though no actual battles occurred throughout the Cold War, there was the threat of rival countries launching atomic bombs at each other.

Many people were afraid that a country with atomic bombs would become too powerful and could attempt to build an empire; such as Germany’s attempt at building an empire during World War II. This prompted many people to want to have regulations on atomic bombs. One of the proposed regulations was to put the bombs under the United Nation’s control so no country can try to use the bombs for conquest.

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I address myself to the organization, founded for the purpose to further co-operation between nations on all problems of common concern, with some considerations regarding the adjustment of international relations required by modern development of science and technology. At the same time as this development holds out such great promises for the improvement of human welfare it has, in placing formidable means of destruction in the hands of man, presented our whole civilization with a most serious challenge. Open Letter to the United Nations by Niels Bohr

The United Nations is an international organization founded in 1945 after the second world war. The organization has four main goals:

  1. To keep peace throughout the world;
  2. To develop friendly relations among nations;
  3. To help nations work together to improve the lives of poor people, to conquer hunger, disease and illiteracy, and to encourage respect for each other’s rights and freedoms;
  4. To be a centre for harmonizing the actions of nations to achieve these goals.

When the United Nations first formed, there was only fifty-one countries in the organization. Today there is 193.

The development of atomic warfare would take huge steps forward at the turn of the 20th century:

In the early 1900’s, huge advancements in Atomic Physics took place. One of these is when Bohr concluded that breaking down the nucleus of an atom could release atomic energy. In 1934, Enrico Fermi was able to break down atoms by spraying them with neutrons; a similar experiment occurred in 1938 when Otto Hahn and Fritz Strassman broke down an uranium atom, turning atoms into energy. Not only did this lead to the development of atomic bombs, but it also proved Einstein’s mass-energy equivalence forumla, E=MC2.

With these scientific discoveries and Germany’s nuclear program already in development, Einstein wrote a letter to President Roosevelt in 1939 asking him to start a nuclear program. However, Einstein would come to regret this decision, stating:

I made one great mistake in my life, when I signed the letter to President Roosevelt recommending that atoms bombs be made.

This letter led to what is known as the Manhattan Project. The Manhattan Project was a research project that was funded over $2 billion dollars in order to figure out how to build an atomic bomb. One of the scientists who worked on this project was Bohr himself. The project started in 1942, and in 1945, the first atomic bomb would be used.

On August 6th, 1945, an American plane dropped an atomic bomb, dubbed Little Boy, on Hiroshima, Japan. Only three days later, another atomic bomb, named Fat Man, would be dropped on Nagasaki, Japan. These two bombs killed over 215,000 people, many of the casualties being civilians.

Mushroom cloud over Nagasaki.

Destruction as a result of the bombs.

A post-war model of Little Boy.

It is very important to note that many scientists didn’t want the atomic bomb to built as a means of catastrophic destruction, but rather to reap the many benefits of being able to build one and the knowledge that comes with it.

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