the
Atomic Bombing of Hiroshima
At 8:15 on
the morning of August 6, 1945, the United States Army Air
Forces dropped the nuclear weapon "Little Boy" on the city
of Hiroshima, followed three days later by the detonation of
the "Fat Man" bomb over Nagasaki, Japan. In his 1999 book
Downfall, historian Richard Frank analyzed the many widely
varying estimates of casualties caused by the bombings. He
concluded "The best approximation is that the number is huge
and falls between 100,000 and 200,000." Most of the
casualties were civilians.
The role of the bombings in Japan's surrender, as well as
the effects and justification of them, have been subject to
much debate. In the U.S., the prevailing view is that the
bombings ended the war months sooner than would otherwise
have been the case, saving many lives that would have been
lost on both sides if the planned invasion of Japan had
taken place. In Japan, the general public tends to think
that the bombings were needless as the preparation for the
surrender was in progress in Tokyo.
Prelude to
the bombings
The United
States, with assistance from the United Kingdom and Canada,
designed and built the bombs under the codename Manhattan
Project; initially for use against Nazi Germany and inspired
by the correct assumption that Germany would also conduct an
atomic bomb project, and incorrect assumption that the Nazis
held a lead in atomic weapons research. The first nuclear
device, called "Gadget," was tested near Alamogordo, New
Mexico on July 16, 1945. The Hiroshima and Nagasaki bombs
were the second and third to be detonated and the only ones
ever employed as weapons.
Hiroshima and Nagasaki weren't the first times that the
Allies had bombed Axis cities without specifically targeting
military installations, nor the first time that such
bombings had caused huge numbers of civilian casualties, nor
the first time that such bombings were (or came to be)
controversial. In Germany, the Allied firebombing of Dresden
resulted in roughly 30,000 deaths. The March 1945
firebombing of Tokyo may have killed as many as 100,000
people. By August, about 60 Japanese cities had been
destroyed through a massive aerial campaign, including large
firebombing raids on the cities of Tokyo and Kobe.
Over 3½ years of direct U.S. involvement in World War II,
approximately 400,000 American lives had been lost, roughly
half of them incurred in the war against Japan. In the
months prior to the bombings, the Battle of Okinawa resulted
in an estimated 50–150,000 civilian deaths, 100–125,000
Japanese or Okinawan military or conscript deaths and over
72,000 American casualties. An invasion of Japan was
expected to result in casualties many times greater than in
Okinawa.
U.S. President Harry S. Truman, who was unaware of the
Manhattan Project until Franklin Roosevelt's death, made the
decision to drop the bombs on Japan. His stated intention in
ordering the bombings was to bring about a quick resolution
of the war by inflicting destruction, and instilling fear of
further destruction, that was sufficient to cause Japan to
surrender. On July 26 Truman and other allied leaders issued
The Potsdam Declaration outlining terms of surrender for
Japan:
"...The might that now converges on Japan is immeasurably
greater than that which, when applied to the resisting
Nazis, necessarily laid waste to the lands, the industry and
the method of life of the whole German people. The full
application of our military power, backed by our resolve,
will mean the inevitable and complete destruction of the
Japanese armed forces and just as inevitably the utter
devastation of the Japanese homeland..."
"...We call upon the government of Japan to proclaim now the
unconditional surrender of all Japanese armed forces, and to
provide proper and adequate assurances of their good faith
in such action. The alternative for Japan is prompt and
utter destruction."
The next day, Japanese papers reported that the declaration,
the text of which had been broadcast and dropped on leaflets
into Japan, had been rejected. The atomic bomb was still a
highly guarded secret and not mentioned in the declaration.
Choice of
targets
Secretary of War Henry L. Stimson struck Kyoto from the list
because of its cultural significance, over the objections of
Gen. Leslie Groves, head of the Manhattan Project. According
to Professor Edwin O. Reischauer, Stimson "had known and
admired Kyoto ever since his honeymoon there several decades
earlier." On July 25 General Carl Spaatz was ordered to bomb
one of the targets: Hiroshima, Kokura, Niigata or Nagasaki
as soon after August 3 as weather permitted, and the
remaining cities as additional weapons became available.
Hiroshima
At the time
of its bombing, Hiroshima was a city of considerable
industrial and military significance. Even some military
camps were located nearby, such as the headquarters of the
Fifth Division and Field Marshal Shunroku Hata's 2nd General
Army Headquarters, which commanded the defence of all of
southern Japan. Hiroshima was a minor supply and logistics
base for the Japanese military. The city was a
communications centre, a storage point, and an assembly area
for troops. It was one of several Japanese cities left
deliberately untouched by American bombing, allowing an
ideal environment to measure the damage caused by the atomic
bomb. Another account stresses that after General Spaatz
reported that Hiroshima was the only targeted city without
POW-camps, Washington decided to assign it highest priority.
The centre of the city contained a number of reinforced
concrete buildings and lighter structures. Outside the
centre, the area was congested by a dense collection of
small wooden workshops set among Japanese houses. A few
larger industrial plants lay near the outskirts of the city.
The houses were of wooden construction with tile roofs, and
many of the industrial buildings also were of wood frame
construction. The city as a whole was highly susceptible to
fire damage.
The population of Hiroshima had reached a peak of over
381,000 earlier in the war, but prior to the atomic bombing
the population had steadily decreased because of a
systematic evacuation ordered by the Japanese government. At
the time of the attack the population was approximately
255,000. This figure is based on the registered population
used by the Japanese in computing ration quantities, and the
estimates of additional workers and troops who were brought
into the city may be inaccurate.
The bombing
A postwar "Little Boy" casing mockup
Hiroshima
was the primary target of the first U.S. nuclear attack
mission, on August 6, 1945. The B-29 Enola Gay, piloted and
commanded by Colonel Paul Tibbets, was launched from Tinian
airbase in the West Pacific, approximately 6 hours' flight
time away from Japan. The drop date of the 6th was chosen
because there had previously been a cloud formation over the
target. At the time of launch, the weather was good, and the
crew and equipment functioned properly. Navy Captain William
Parsons armed the bomb during the flight, since it had been
left unarmed to minimize the risks during takeoff. In every
detail, the attack was carried out exactly as planned, and
the gravity bomb, a gun-type fission weapon, with 60 kg (130
pounds) of uranium-235, performed precisely as expected.
About an
hour before the bombing, the Japanese early warning radar
net detected the approach of some American aircraft headed
for the southern part of Japan. The alert had been given and
radio broadcasting stopped in many cities, among them
Hiroshima. The planes approached the coast at a very high
altitude. At nearly 08:00, the radar operator in Hiroshima
determined that the number of planes coming in was very
small—probably not more than three—and the air raid alert
was lifted. (To save gasoline, the Japanese had decided not
to intercept small formations, which were assumed to be
weather planes.) The three planes present were the Enola Gay
(named after Colonel Tibbets' mother), The Great Artiste (a
recording and surveying craft), and a then-nameless plane
later called Necessary Evil (the photographing plane). The
normal radio broadcast warning was given to the people that
it might be advisable to go to air-raid shelters if B-29s
were actually sighted, but no raid was expected beyond some
sort of reconnaissance. At 08:15, the Enola Gay dropped the
nuclear bomb called "Little Boy" over the centre of
Hiroshima. It exploded about 600 meters (2,000 feet) above
the city with a blast equivalent to 13 kilotons of TNT,
killing an estimated 70–80,000 people. At least 11 U.S. POWs
also died.[6] Infrastructure damage was estimated at 90% of
Hiroshima's buildings being either damaged or completely
destroyed.
Japanese realization of the bombing
The Tokyo
control operator of the Japanese Broadcasting Corporation
noticed that the Hiroshima station had gone off the air. He
tried to re-establish his program by using another telephone
line, but it too had failed. About twenty minutes later the
Tokyo railroad telegraph centre realized that the main line
telegraph had stopped working just north of Hiroshima. From
some small railway stops within ten miles (16 km) of the
city came unofficial and confused reports of a terrible
explosion in Hiroshima. All these reports were transmitted
to the Headquarters of the Japanese General Staff.
Military bases repeatedly tried to call the Army Control
Station in Hiroshima. The complete silence from that city
puzzled the men at Headquarters; they knew that no large
enemy raid had occurred and that no sizeable store of
explosives was in Hiroshima at that time. A young officer of
the Japanese General Staff was instructed to fly immediately
to Hiroshima, to land, survey the damage, and return to
Tokyo with reliable information for the staff. It was
generally felt at Headquarters that nothing serious had
taken place, that it was all a terrible rumour starting from
a few sparks of truth.
The staff officer went to the airport and took off for the
southwest. After flying for about three hours, while still
nearly 100 miles (160 km) from Hiroshima, he and his pilot
saw a great cloud of smoke from the bomb. In the bright
afternoon, the remains of Hiroshima were burning. Their
plane soon reached the city, around which they circled in
disbelief. A great scar on the land still burning, and
covered by a heavy cloud of smoke, was all that was left.
They landed south of the city, and the staff officer, after
reporting to Tokyo, immediately began to organize relief
measures.
The burns on this victim look like the kimono patterns; the
lighter areas of the cloth reflected the intense light from
the bomb, causing less damage
Tokyo's
first knowledge of what had really caused the disaster came
from the White House public announcement in Washington,
sixteen hours after the nuclear attack on Hiroshima.
Radiation poisoning and/or necrosis caused illness and death
after the bombing in about 1% of those who survived the
initial explosion. By the end of 1945, thousands more people
died due to radiation poisoning, bringing the total killed
in Hiroshima in 1945 to about 90,000. Since then about a
thousand more people have died of radiation-related causes.
(According to the city of Hiroshima, as of August 6, 2005,
the cumulative death toll among Hiroshima's atomic-bomb
victims was 242,437. That figure includes everyone who was
in the city when the bomb exploded, or was later exposed to
fallout, who has since died.)
Survival of
some structures
Some of the
reinforced concrete buildings in Hiroshima were very
strongly constructed because of the earthquake danger in
Japan, and their framework did not collapse even though they
were fairly close to the centre of damage in the city. As
the bomb detonated in the air, the blast was more downward
than sideways, which was largely responsible for the
survival of the Prefectural Industrial Promotional Hall, now
commonly known as the Genbaku, or A-bomb Dome designed and
built by the Czech architect Jan Letzel, which was only a
few meters from ground zero. (The ruin was named Hiroshima
Peace Memorial and made a UNESCO World Heritage site in 1996
over the objections of the U.S. and China.)
Events of
August 7-9
After the
Hiroshima bombing, President Truman announced, "If they do
not now accept our terms, they may expect a rain of ruin
from the air the likes of which has never been seen on this
earth." On August 8, 1945, leaflets were dropped and
warnings were given to Japan by Radio Saipan. (The area of
Nagasaki did not receive warning leaflets until August 10,
though the leaflet campaign covering the whole country was
over a month into its operations.) An English translation of
that leaflet is available at PBS.
At one minute past midnight on August 9, Tokyo time, Russian
infantry, armour, and air forces launched an invasion of
Manchuria. Four hours later, word reached Tokyo that the
Soviet Union had broken the neutrality pact and declared war
on Japan. The senior leadership of the Japanese Army took
the news in stride, grossly underestimating the scale of the
attack. They did start preparations to impose martial law on
the nation, with the support of Minister of War Anami, in
order to stop anyone attempting to make peace.
Responsibility for the timing of the second bombing was
delegated to Colonel Tibbets as commander of the 509th
Composite Group on Tinian. Scheduled for August 11 against
Kokura, the raid was moved forward to avoid a five day
period of bad weather forecast to begin on the 10th.
Nagasaki
Urakami Tenshudo (Catholic Church in Nagasaki) destroyed by
the atomic bomb, the dome of the church having toppled off.
The city of
Nagasaki had been one of the largest sea ports in southern
Japan and was of great wartime importance because of its
wide-ranging industrial activity, including the production
of ordnance, ships, military equipment, and other war
materials.
In contrast to many modern aspects of Nagasaki, the bulk of
the residences were of old-fashioned Japanese construction,
consisting of wood or wood-frame buildings, with wood walls
(with or without plaster), and tile roofs. Many of the
smaller industries and business establishments were also
housed in buildings of wood or other materials not designed
to withstand explosions. Nagasaki had been permitted to grow
for many years without conforming to any definite city
zoning plan; residences were erected adjacent to factory
buildings and to each other almost as closely as possible
throughout the entire industrial valley.
Nagasaki had never been subjected to large-scale bombing
prior to the explosion of a nuclear weapon there. On August
1, 1945, however, a number of conventional high-explosive
bombs were dropped on the city. A few hit in the shipyards
and dock areas in the southwest portion of the city, several
hit the Mitsubishi Steel and Arms Works and six bombs landed
at the Nagasaki Medical School and Hospital, with three
direct hits on buildings there. While the damage from these
bombs was relatively small, it created considerable concern
in Nagasaki and a number of people—principally school
children—were evacuated to rural areas for safety, thus
reducing the population in the city at the time of the
nuclear attack.
To the north of Nagasaki there was a camp holding British
prisoners of war. They were working in the coal mines so
consequently only found out about the bombing when they came
to the surface. For them, it was the bomb that saved their
lives. However at least eight known POWs were causalities.
The bombing
A Japanese report on the bombing characterized Nagasaki as
"like a graveyard with not a tombstone standing."
On the
morning of August 9, 1945, the crew of the American B-29
Superfortress Bock's Car, flown by Major Charles W. Sweeney
and carrying the nuclear bomb code-named "Fat Man," found
their primary target, Kokura, to be obscured by clouds.
After three runs over the city and having fuel running low
due to a fuel-transfer problem, they headed for their
secondary target, Nagasaki. At about 07:50 Japanese time, an
air raid alert was sounded in Nagasaki, but the "all clear"
signal was given at 08:30. When only two B-29
Superfortresses were sighted at 10:53 the Japanese
apparently assumed that the planes were only on
reconnaissance and no further alarm was given.
A few minutes later, at 11:00, the observation B-29 (The
Great Artiste flown by Captain Frederick C. Bock) dropped
instruments attached to three parachutes. These instruments
also contained messages to Prof. Ryokichi Sagane, a nuclear
physicist at the University of Tokyo who studied with three
of the scientists responsible for the atomic bomb at the
University of California, Berkeley, urging him to tell the
public about the danger involved with these weapons of mass
destruction. The messages were found by military
authorities, but not turned over to Sagane.
A post-war "Fat Man" model
The hibakusha
The
survivors of the bombings are called hibakusha (被爆者), a
Japanese word that literally translates to "people exposed
to the bomb". The suffering of the bombing is the root of
Japan's postwar pacifism, and the nation has sought the
abolition of nuclear weapons from the world ever since. As
of 2006, there are about 266,000 hibakusha still living in
Japan. |