How scientists learned to stop worrying and love the bomb *
A topic in 'Science & Ethics'
The design and development of weapons involves the application of science. Many scientist work in this area – looking to make weapons more powerful, more accurate, more (or less) discriminating, more difficult to protect against, etc. Many areas of weaponry are subject to international agreements about development and/or use, e.g. biological and chemical weapons, and so forth.
The case of the first atomic weapons is noteworthy as it was surely the first time that governments sanctioned the development of indiscriminate weapons of mass destruction with the support of many scientists.
Manhattan and Trinity
Famously, the 'Manhattan Project' was based in the United States during the second world war when the 'allies' (UK and many Commonwealth countries, many European Countries, and the US) fought the 'axis' powers (German, Italy, Japan) after Germany had invaded many other European nations, and later Japan had attacked the US Fleet at Pearl Harbour at Oahu, Hawaii.
The Manhattan Project recruited many scientists who believed that it was possible to build a massive bomb from fissile material; and that helping to develop such a bomb was justified in the context of the war. As well as Americans, the project involved many European scientists, including some who had fled the Germany, or German occupied countries, because under Nazi Racial laws they would be defined Jews** and subject to imprisonment and even (as later became clear) extermination.
The spectre of the Nazis wining the war was considered by many scientists as a greater evil than building an atomic bomb that could be used against them. (Of course, every person had their individual motivations and values – for some obedience to the authority of the government might have been enough to persuade them to take up such war work. See 'An experiment on memory?'.)
In scientific and technical terms the Project was a success, building a workable atomic bomb just a few years after the theoretical possibility of such a weapon had become clear.
The first atomic bomb (on Earth at least!), based on plutonium, was exploded on 16th July 1945 in the dessert of New Mexico. The test, known as Trinity, was a success. After observing this (from what was judged a safe distance) the Manhattan Project director, physicist J. Robert Oppenheimer, is supposed to have quoted words form the ancient Indian sacred text, Bhagavad Gita:
"Now I am become Death, the destroyer of worlds"
Despite the technical success, the war in Europe had already ended in May 1945 after Germany surrendered to the Allies – so the weapon was too late in that regard. The threat that the Nazis had in parallel been designing their own atomic bomb, and might succeed first, turned out to be unfounded. (There was a German nuclear research programme, but without full support of the leadership, divided into multiple groups, and carried out by scientists who doubted a bomb was feasible at that time-and at least some of whom did not want the Nazis to acquire such a weapon.)
However the war continued in the Pacific where Japan continued fighting when its German ally surrendered and the war ended in Europe.
Hiroshima and Nagasaki
Japan, like Germany, had invaded a number of neighbouring countries, and seemed determine to continue the war in its region regardless of what had occurred elsewhere. Japan had already been subject to extensive bombing campaigns with conventional weapon.
The US government (with the agreement of the UK that has supported the Manhattan Project) decided to use the new atomic weapons over Japan. On 6th August 1954, a uranium-based bomb called ironically 'Little Boy' was exploded over the city of Hiroshima. (The bombs were considered to be more effective when exploding in the air rather than on landing).
"With the explosion of the atomic bomb, the epicentre instantaneously reached a maximum temperature of several million degrees centigrade and an atmospheric pressure of several 100, 000 bars; with the formation of a fireball, powerful heat rays and radiation were emitted in all directions within a short interval. Radiation extended not only directly from the burst point but also form the surface of the ground-from fission fragments and the residue of neutron-induced radioactive materials. The shock waves propagated by the explosion and the tremendous blast that followed almost instantaneously demolished buildings and killed many people. The survivors suffered the agonies of thermal burns and radiation exposure whose effects were in many cases delayed."
The Committee for the Compilation of Materials on Damage caused by the atomic bombs in Hiroshima and Nagasaki, 1981
On the 9th August, three days later, a different design of bomb (a plutonium based weapon like that in the Trinity test) was exploded over the City of Nagasaki. The Japanese government formally surrendered on 2nd September.
There is little doubt that the use of the atomic weapons (with the assumption that more cities could be attacked subsequently) brought the war to an end – although there is less agreement on how much longer Japan would have held out without the atomic bombing. Whether the Japanese surrender might have been brought about by inviting senior government and military figures to observe a demonstration, like Trinity, without the massacres in Hiroshima and Nagasaki remains a moot point.
Should scientists work on weapons research? In particular, can developing weapons of mass destruction ever be justified? Did the circumstances of the Second World war, and the evils of Nazism, provide an exceptional context where scientists who would normally refuse to work on weapons development should have made an exception?
Once the bomb had been provided to the military, any decision on whether and/or when and where to use it was outside the control of scientists. Does this mean that politicians must be consider fully responsible for the mass killings and maiming of civilians at Hiroshima and Nagasaki, with scientists being without blame?
"…
Knowledge is a deadly friend
If no one sets the rules
The fate of all mankind, I see
Is in the hands of fools…"
from Pete Sinfield's lyrics for 'Epitaph' (Robert Fripp, Peter John Sinfield, Greg Lake, Ian Mcdonald, Michael Rex Giles) by King Crimson, 1969
Sadly, as true today as when written.
Why was the atomic bomb special?
All weapons of war cause fatalities and horrible injuries.
We might suggest that the atomic bombs were especially nasty because of their scale, and the radioactive nature of the material used.
Indiscriminate killing
Because of the size of the explosion caused by the atomic bombs, they could not be used over cities in targeted attacks on military sites. The bombs certainly destroyed much military resource and killed many soldiers, but inevitably killed and injured many thousands of civilians such as school children. The atomic bombs destroyed homes and civilian infrastructure such as schools and fire stations. The target of each bomb was a city, and its people.
"In the atomic bombings of Hiroshima and Nagasaki, the ground surface at the hypocentre is believed to have reached a temperature of 3,000˚ to 4,000˚ C. The heat rays caused thermal burns on the exposed skin of people within the limits of about 3.5 kilometres of the hypocentre in Hiroshima and of about 4 kilometres in Nagasaki…
The total area reduced to ashes by blasts and fires was about 13 square kilometres in Hiroshima and about 6.7 square kilometres in Nagasaki."
The Committee for the Compilation of Materials on Damage caused by the atomic bombs in Hiroshima and Nagasaki, 1981
However, this does not make the atomic bomb unique, as similar effects were achieved by mass bombings of cities. Some months before the atomic bombings, an air raid on Tokyo in a single night led to an extensive firestorm that is thought to have killed 80 000 to 100 000 people and left a million people homeless. This again was an indiscriminate attack on a city and its people (and reflected some of the blanket bombing attacks on German cities such as Dresden). The Tokyo raid involved hundreds of planes dropping many bombs-whereas Hiroshima and Nagasaki were each devastated by a single bomb from a single plane (in each case supported by a second plane sent ahead to check on weather conditions).
Radioactive fall-out
What was new with the atomic bombs was the use of radioactive materials as weapons. Clearly radioactivity was inherent to the nature of the bomb (the explosion was caused by a runaway nuclear reaction), and ionising radiation was released in the explosion.
But radiation was not just due to the fissile material used in the bomb, and the daughter isotopes produced in the fission process, but also newly radioactive materials generated by the irradiation of the material present in the vicinity of the explosion. As a result, the environment was contaminated with a wide range of different radioactive isotopes, some with very short half-lives (which would irradiate survivors immediately) and some with much longer half-lives, which would continue to release radiation for a long time (i.e., years) after the attack.
"In a conflagration the minute particles of carbon produced by fire and others are blown up into the cold air, where water vapour is formed , and rain may be precipitated. Between 9 a.m. and 4 p.m. in Hiroshima, 'black rain' containing radioactivity poured down over a large area from north of the hypocentre to the west…Also, in Nagasaki, the 'black rain' came down on the Nishiyama district, located east of the hypocentre [sic], about 20 minutes after the explosion."
The Committee for the Compilation of Materials on Damage caused by the atomic bombs in Hiroshima and Nagasaki, 1981
The atomic bombs therefore polluted the atmosphere, land and waterways with radiation, some of it long-lasting. Clearly the atmosphere is continuous over the earth, so although much of the radioactivity fell down on the targeted cities, some would have been widely dispersed. Atomic bombs are to some extent then weapons with potential to harm people (and animals and plants) far beyond the target.
Not only can the radioactivity released not be contained, but its effects can be immediate (fatal exposure) or deferred. Using nuclear weapons means killing some people immediately, making others ill in ways that lead to slow deaths, and initiating a process that will lead to people becoming ill years, even decades after the attack: indeed because of the potential to damage genetic material, an atomic bomb leads to casualties in subsequent generations. Many people not born till years after the end of the war suffered from conditions due to the exposure of their parents.
"On August 9, 1945, the city of Nagasaki turned into an inferno beyond human imagination, and more than 70,000 precious lives were obliterated.
Even now, 35 years on form that event, a great number of surviving victims are still suffering under the persistent shadow of death."
Hitoshi Motoshima, Mayor of Nagasaki, August 1980
Are there special ethical considerations to using a weapon that will cause medical conditions that only develop years after the end of the conflict in which it is used?
The hydrogen bomb
The fission bombs dropped on Japan in 1945 were weapons of mass destruction, at a scale never seen before. After the end of the second world war the development of nuclear weapons continued, and much more powerful bombs were developed. During the Manhattan project the physicist Edward Teller had argued, and started developing, a fusion-based 'super' atomic bomb- what became known as a hydrogen bomb.
The first hydrogen bomb was tested in 1952. The hydrogen bomb is a 'thermonuclear' weapon on a much vaster scale, such that bombs of the type used against Japan are used as fuses simply to set of the bombs. A hydrogen bomb uses nuclear fusion (as takes place in stars like the sun), and the fission device produced the vast temperatures are which fusion will occur.
The hydrogen bomb has been characterised as a weapon without a proper potential military target, as it would cause destruction and fall-out over such a vast area. At the time of the first development of such weapons, at which time there was a so-called 'cold war' between the United States and Soviet Union, many argued that such weapons fitted a notion known as 'mutually assured destruction' (sic, MAD) in that neither side would ever launch an attack on the other, as the result would surely be the effective destruction of both countries, with millions dead and all major civic centres destroyed.
Are there any ethical arguments for building weapons capable of causing destruction at a scale hundreds or thousands of times greater than that seen at Hiroshima and Nagasaki? Is there scientific value in demonstrating that such weapons can be built?
A world living with nuclear weapons
International agreements sought to prevent nuclear proliferation beyond the first five nations to acquire weapons (that is, the permanent members of the UN Security Council: USA, USSR {as was: with an arsenal now under the control of the Russian Federation}, UK, China and France. However it is now believed a number of other countries have acquired nuclear arsenals. Many scientists have been involved in arguing for non-proliferation of nuclear weapons, for international regulation and inspection regimes (as per the 2015 International agreement with Iran to monitor its nuclear programme, prior to the US withdrawing in 2018), even for total nuclear disarmament. But if the task assigned to the Manhattan project of developing a functioning atomic weapon seemed a challenge at the time: it proved far easier than the challenge of ridding the world of the nuclear arsenals once they were in place.
** That is to say, this not only included people who would self-identify as Jews, but also some people who had never considered themselves as Jewish, and others who had previously converted from Judaism to Christianity for example. Under Nazi ideology, being Jewish was not a religious identify that could be adopted or forsaken, but an inherent property linked to the folk-notion of 'blood line'.
Such unscientific ideas have traditionally not only underpinned racist ideologies, such as Nazism, but have also supported notions of some people having 'more noble' blood. So, for example, the United Kingdom is Monarchy where the right to be sovereign is based on blood-line rather than any inherent merit (or merit as perceived by the wider population) of the person crowned Queen or King. (The UK is now a democracy where the Sovereign is guided by the elected government, such that should the King refuse to give Royal assent to a law passed in the Parliament this would precipitate a constitutional crisis. Historically, however, the Sovereign was seen to have been been somehow appointed by God and had more absolute powers.)
* This is a reference to the Kubrick film 'Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb' starring Peter Sellers as (inter alia) nuclear expert Dr Strangelove, a former Nazi scientist now advising the American president during the cold war.
Sources cited:
- Motoshima, Hitoshi (1980) The City of Nagasaki, Peace Declaration, reproduced in Hiroshima and Nagasaki. The physical, medical, and social effects of the atomic bombings, 1981 (Translated by Eisei Ishikawa & David L. Swain). Hutchinson & Co. (Publishers)
- The committee for the compilation of materials on damage caused by the atomic bombs in Hiroshima and Nagasaki (1981) Hiroshima and Nagasaki. The physical, medical, and social effects of the atomic bombings. (Translated by Eisei Ishikawa & David L. Swain). Hutchinson & Co. (Publishers)
