R e s p o n s e
G r o u p
Assessing the Decision
to Build and Use the
Atomic Bomb
Overview
This Response Group activity allows students to explore decisions the U.S.
government made about the atomic bomb during World War II. Groups discuss
three decisions about the bomb that the U.S. government faced: whether to build
the bomb, whether to drop the bomb, and whether, in hindsight, Truman made
the right decision when he authorized the use of atomic weapons. For each
decision, students study visual and written information to make a choice from
several options. Afterward, students take part in a class discussion to critically
analyze the repercussions of the decision to drop the atomic bomb.
A C T I V I T Y
14
Materials
• Transparencies
14A–14C
• Student Handout 14A
Procedures at a Glance
• Before class, decide how you will divide students into heterogeneous groups
of three. Use the diagram at right to determine where students should sit.
• In class, direct students to move into their correct places. Explain that they
will learn about decisions the U.S. government made about the atomic bomb
during World War II.
• Use the information given in Procedures in Detail to introduce students to
developments in atomic physics in the years leading up to World War II.
• Pass out Student Handout 14A, and then project Transparency 14A. Have
students carefully examine the transparency and read about Decision A on
the handout. Answer any questions they have about the decision.
• Have students read Critical Thinking Question A, closely examine the transparency, and use the information on the handout to discuss the options. Have
them record their answer on the handout.
• Next, appoint a Presenter in each group to share the group’s answer with the
class. Use the Teacher’s Guide to reveal the decision that the government
actually made.
• Repeat this process for the two remaining decisions. Rotate who takes on the
role of Presenter for each decision.
• Finally, hold a class discussion about the decision to drop the atomic bomb.
15
P r o c e d u r e s
Procedures in Detail
1 Before class, decide how you will divide students into heterogeneous groups
of three. Use the diagram found below the Materials List to determine where
students should sit.
2 In class, direct students to move into their correct places. Then explain that in
this activity, students will learn about decisions the U.S. government made
about the atomic bomb during World War II.
I d e a
f o r
S t u d e n t
R e s p o n s e
To preview this activity, tell students that people often have to choose
between achieving an important goal by doing something they do not
want to do and not achieving the goal. As an example, ask the students to
imagine that they are collecting contributions to raise money for AIDS
research but realize they will get more and larger donations if they lie and
say they are collecting for something broader, such as research on all lifethreatening diseases. In their notebooks, have each student write a short
answer to this question: Is it wrong to lie even if the motivation is good,
or do the ends justify the means?
Have several students share their answers. Then have all students copy
the spectrum below in their notebooks and place an X on it to indicate
their answer to this question: How often do the ends justify the means?
Ask students to write a paragraph describing a real or hypothetical
example to support their answers.
X
Always
Usually
Sometimes
Rarely
Never
3 Use the following information to introduce students to developments in
atomic physics in the years leading up to World War II:
World War II began when Germany invaded Poland on September 1,
1939. Within 10 months, Hitler’s Nazi forces had conquered most of the
continent of Europe, including France, Belgium, the Netherlands, Norway,
Poland, Czechoslovakia, and Austria (which Germany had taken control
of in 1938).
At about the same time, a new threat emerged—the possibility that Germany was developing an atomic bomb. Science fiction writers like H. G.
Wells had been writing about atomic weaponry and power since 1900. By
the late 1930s, science had begun to catch up with fiction as experiments
in atomic physics began to reap success.
The threat of a German atomic bomb project necessitated action on the
part of the United States and its allies. The decisions and actions taken to
16
Activity 14
P r o c e d u r e s
counter the Nazi threat are considered some of the most controversial in
history. These decisions played an important role in the outcome of World
War II and changed the course of world history.
4 Pass out Student Handout 14A: [Decisions]. Project Transparency 14A,
which shows physicist Albert Einstein answering questions during a lecture.
Have students carefully examine the transparency and read the information
about Decision A on the handout. Answer any questions they have.
5 Once students understand the information about Decision A, have them read
Critical Thinking Question A. Encourage them to closely examine the transparency and use the information on the handout to discuss the options listed.
Give students adequate time—about 5 to 7 minutes—to discuss the question
and record their answer on the handout.
Student Handout 14A
6 When groups have finished recording their answers, appoint a Presenter for
each group. Ask Presenters to share their group’s answer with the class.
Encourage them to point out details in the transparency or information on
Student Handout 14A that helps explain their group’s choice. Then use the
Teacher’s Guide to reveal the decision the U.S. government actually made.
7 Repeat this process for the two remaining decisions. Rotate who takes on the
role of Presenter for each decision.
Transparencies 14A–14C
Wrap Up
After students have discussed all three decisions, hold a class discussion about
the decision to drop the atomic bomb. Focus on the following questions:
• Was the decision to drop the bomb a military necessity? If not, was it
justifiable for a reason besides military necessity?
• Why do you think atomic weapons have not been used since World War II?
What is the likelihood that they will be used in the future?
I d e a
f o r
S t u d e n t
R e s p o n s e
In their notebooks, have students draw heads and facial expressions
reflecting each of the following people’s reaction to the dropping
of the atomic bomb on Hiroshima and Nagasaki:
•
•
•
•
•
What a relief. I thought
I was going to have to go
and invade Japan.
a U.S. soldier preparing to invade Japan
a Japanese civilian
a scientist who helped create the bomb
Josef Stalin
the student
Have students write a thought bubble above each
head that explains the reaction. A completed U.S.
soldier might look like this:
Assessing the Decision to Build and Use the Atomic Bomb
17
Te a c h e r ’ s
G u i d e
Decision A:
Whether to Build an Atomic Bomb
On July 16, 1945, scientists tested the “gadget” in
a desert near Alamogordo, New Mexico. Before dawn,
they set off the first atomic bomb in history. The explosion first emitted a flash of bright light, a heat wave, and
a fast-moving fireball; then a mushroom-shaped cloud
rose eight miles into the desert sky. The sound of the
explosion was so strong that people heard it 100 miles
away, and the force of it shattered windows 125 miles
away. The blast left a shallow but 1,200-foot-wide crater
in the earth. In short, the test was a success.
Decision B:
Whether to Drop an Atomic BombIn
In Transparency 14A, we see physicist Albert Einstein
answering questions.
In 1939, Roosevelt decided to support research aimed at
creating an atomic bomb. Scientists’ progress was slow
at first. However, in the spring of 1940, British scientists
reported finding a process by which one could realistically develop an atomic bomb. Their announcement convinced Roosevelt and his advisors to commit fully to the
development of the new weapon.
The Manhattan Project—the code name for the
U.S. project to build an atomic bomb—involved the
efforts of about 125,000 Americans, most of whom did
not know exactly what they were working on due to the
strict secrecy surrounding the project. The government
set up large facilities in Hanford, Washington, Oak
Ridge, Tennessee, and Los Alamos, New Mexico, and
invested more than $2 billion in the Manhattan Project.
For almost three years, the largest team of scientists the
world had ever known worked feverishly to produce an
atomic bomb.
Both Enrico Fermi and Niels Bohr—two foreignborn scientists who had moved to the United States—
played an important role in the ultimate success of the
project. Although no formal decisions were made, both
Roosevelt and British prime minister Winston Churchill
assumed that any atomic weapon the scientists developed
would be used to hasten the end of the war.
18
Activity 14
Transparency 14B, we see Harry S. Truman being sworn
in as president after Franklin D. Roosevelt’s death on
April 12, 1945.
On August 6, 1945, an American B-29 plane called the
Enola Gay dropped an atomic bomb on Hiroshima, a
medium-size Japanese city. The five-ton weapon, nicknamed “Little Boy,” exploded with tremendous force
1,900 feet above the city.
Looking down from the plane, American airmen
viewed a scene of destruction and death. One of the
pilots later recalled, “As the bomb fell over Hiroshima
and exploded, we saw an entire city disappear. I wrote
in my log the words: ‘My God, what have we done?’”
The blast instantly killed at least 70,000 people; thousands more died as a result of injuries.
Te a c h e r ’ s
On August 9, the United States dropped a second
atomic bomb, flattening the central part of the city of
Nagasaki and resulting in at least 60,000 more deaths.
On the same day, Soviet forces crossed into Manchuria
and pushed the Japanese army back. Japan surrendered
five days later. The terms of the surrender allowed the
emperor to remain as a symbolic figurehead of the
Japanese government.
The effects of these atomic bombs on Hiroshima
and Nagasaki were truly horrific. The temperature at the
center of the blasts reached over 100 million degrees
Fahrenheit. People located at the centers were instantly
vaporized. People farther from the centers received
deadly burns.
One survivor described the experience this way:
“The appearance of the people was . . . well, they all
had skin blackened by burns. . . . They had no hair
because their hair was burned, and at a glance you
couldn’t tell whether you were looking at them from
in front or in back. . . . Their skin—not only on their
hands, but on their faces and bodies too—hung down.”
Another young man described what he saw: “Everything
I saw made a deep impression—a park nearby covered
with dead bodies waiting to be cremated . . . very badly
injured people evacuated in my direction. . . . The most
impressive thing I saw was some girls, very young girls,
not only with their clothes torn off but with their skin
peeled off as well. . . . My immediate thought was that
this was like the hell I had always read about.”
Weeks and even months later, people died from
radiation poisoning. The victims lost their hair, vomited,
and grew increasingly weak until they died. The bombing was indiscriminate—schoolchildren, the elderly in
hospital beds, mothers and babies, and even some U.S.
prisoners of war being held prison in Hiroshima were all
killed in the blasts.
Truman was returning from the Potsdam conference aboard the battleship Augusta when he received
the news of the destruction at Hiroshima. He exclaimed,
“This is the greatest thing in history!” When the press
raised the moral implications of the bombings, Truman
defended his decision, saying, “We have used it against
those who attacked without warning at Pearl Harbor . . .
G u i d e
against those who have abandoned the pretense of obeying international laws of warfare. We have used it to
shorten the agony of war, in order to save the lives of
thousands and thousands of young Americans.”
Decision C:
Whether Truman Made the Right Decision
In Transparency 14C, we see three images. On the left is
a Japanese atomic bomb victim with the design of the
kimono she had been wearing at the time of the attack
showing on her back. On the right are aerial views of
Nagasaki before and after the atomic bomb was dropped
just after 11:00 A.M. on August 9, 1945.
Historians and members of the public continue to debate
Truman’s decision to drop the atomic bomb. Truman
himself defended the decision until his death. Secretary
of War Henry Stimson and the general in charge of the
Manhattan Project, Leslie Groves, agreed. However,
many of the scientists who worked on the development
of the bomb had misgivings. After the successful test
of the bomb at Alamogordo, New Mexico, J. Robert
Oppenheimer—the scientist in charge of the Manhattan
Project—famously quoted the Hindu epic, the Bhagavad
Gita: “I am become death, the destroyer of worlds.”
After World War II, Oppenheimer became active in
the failed effort to place atomic weapons research and
facilities under international control. Albert Einstein,
who seemed to have started it all with his letter to
Roosevelt, regretted having sent the correspondence.
Assessing the Decision to Build and Use the Atomic Bomb
19
Te a c h e r ’ s
G u i d e
That Albert Einstein—a great pacifist—would provide
the impetus for the development of atomic weapons is
one of history’s greatest ironies.
By 1990, the nuclear arsenals of the United States
and the Soviet Union each included tens of thousands of
weapons. By 2006, at least seven countries possessed
nuclear capabilities, and others were working to develop
them. However, no nuclear weapons have been used to
inflict large-scale damage since World War II.
In recent years, the continued threat of the destructive use of nuclear arms has led many nations to focus
on preventing any additional countries from developing
nuclear weapons and significantly reducing the world’s
nuclear arsenal. Such developments have further fueled
the debate over the initial use of an atomic bomb. Some
feel that that action was clearly ethically wrong. Others
feel that the presence of nuclear weapons is the key to
preventing another world war.
20
Activity 14
S t u d e n t
H a n d o u t
1 4 A
Decision A: Whether to Build an Atomic Bomb
In August 1939, Albert Einstein, a brilliant and wellknown physicist, sent President Franklin D. Roosevelt a
letter. In it, Einstein explained recent scientific developments that might mean an atomic bomb could be created.
He went on to urge Roosevelt to investigate that possibility. He also suggested that Germany might already be
building an atomic bomb. The following is an excerpt
from Einstein’s letter:
“In the course of the last four months it has been
made probable—through the work of Joliet in
France as well as Fermi and Szilard in America—
that it may be possible to set up a nuclear chain
reaction in a large mass of uranium [one of the
minerals essential to the construction of an atomic
bomb], by which vast amounts of power and large
quantities of new radium-like elements would be
generated. Now it appears almost certain that this
could be achieved in the immediate future.
“This new phenomenon would also lead to
the construction of bombs, and it is conceivable—
though much less certain—that extremely powerful
bombs of a new type may thus be constructed. A
single bomb of this type, carried by boat and
exploded in a port, might very well destroy the
whole port together with some of the surrounding
territory. However, such bombs might very well
prove to be too heavy for transportation by air.
“I understand that Germany has actually
stopped the sale of uranium from the Czechoslovakian mines which she has taken over. That she
should have taken such early action might perhaps
be understood on the ground that the son of the
German Under-Secretary of State, von Weizsäcker,
is attached to the Kaiser-Wilhelm-Institut in Berlin
where some of the American work on uranium is
now being repeated.”
© Teachers’ Curriculum Institute
When Einstein wrote this letter to Roosevelt, the
United States had not yet entered into war with Germany.
However, the president took immediate interest in the
scientific developments Einstein described. The bomb
would not only be the most powerful weapon on earth,
it would transform warfare by making it possible to kill
more people with much less effort.
In the 18 months after Einstein sent his letter, the
Roosevelt administration debated what action to take to
counter the German threat. Some officials wondered
how serious the threat really was. In addition, not all
scientists agreed with Einstein, and some wondered
whether the bomb could be developed so quickly.
Critical Thinking Question A
You are an advisor to President Roosevelt. Which of
the following do you advise the president to do? Be
prepared to defend your answer.
a. Ignore scientific developments and do not build an
atomic bomb; concentrate U.S. efforts on building
conventional weapons, such as faster planes and
more powerful tanks.
b. Vigorously pursue the construction of an atomic
bomb because the United States is in a race against
Germany.
c. Postpone the development of an atomic bomb and
send spies into Germany to determine the accuracy
of Einstein’s letter.
d. Do not develop an atomic bomb. Instead, monitor
the construction of new German weapons facilities
and then send American bombers to destroy them.
e. Denounce the development of an atomic bomb as
being immoral. Only evil could come from the
development of such a destructive weapon.
Assessing the Decision to Build and Use the Atomic Bomb
21
S t u d e n t
H a n d o u t
1 4 A
Decision B: Whether to Drop an Atomic Bomb
Vice President Harry S. Truman took over the presidency after Roosevelt unexpectedly died in April 1945.
Three months later, while he was attending the Allied
conference in Potsdam, Germany, Truman received a
telegram stating that testing of the atomic bomb had
been successful. By this time in the war, the Allies had
utterly defeated Germany. However, Japan had vowed to
fight on, despite the Allies’ demand at Potsdam of an
unconditional surrender.
The Japanese felt that an unconditional surrender
would jeopardize the position of their emperor, whom
they considered divine. In addition, they viewed surrender as dishonorable. They therefore fought with intense
resistance. Believing it was more honorable to commit
suicide than to surrender to enemy forces, Japanese
kamikaze pilots strapped themselves into planes loaded
with explosives and crashed them into American naval
vessels. They managed to destroy 34 ships and damage
hundreds of others.
Despite these desperate attacks, by July 1945 the
Japanese were nearly defeated. Three factors worked
against them. First, Allied bombing runs over Japan
had killed tens of thousands of civilians and military
personnel. Second, an Allied naval blockade made it
impossible for Japan to import the goods necessary to
continue fighting. It also prevented more than 1 million
Japanese troops stationed in China from returning to
their homeland. Third, the massive Soviet Red Army
was poised to enter the war and assist the United States.
The United States had hoped to end the Pacific
War by invading Japan. However, given the determination of the Japanese, President Truman worried that such
an invasion would cost thousands of American lives.
22
Activity 14
In light of this fear, some of his advisors recommended
ending the war quickly by dropping an atomic bomb
without warning on a large Japanese city.
The undersecretary of the Navy, Ralph Bard, disagreed. He told Truman that dropping the bomb without
a specific warning would jeopardize “the position of the
United States as a great humanitarian nation.” A group
of Manhattan Project scientists suggested an alternate
plan—that the United States drop the bomb in a remote,
unpopulated location to show the bomb’s power and
convince Japan to surrender.
Critical Thinking Question B
You are a close advisor to President Truman. Which of
the following do you advise the president to do? Be
prepared to defend your answer.
a. Without warning, drop an atomic bomb on a
Japanese city as soon as possible.
b. Drop an atomic bomb on an unpopulated area to
demonstrate its destructive capabilities.
c. Warn the Japanese that the United States possesses
atomic weapons and is willing to use them if the
Japanese don’t surrender by a specified time. If they
don’t surrender, then drop an atomic bomb.
d. Reject the use of atomic weapons and continue the
naval blockade and conventional bombing. If the
measures do not produce a Japanese surrender, then
invade Japan.
e. Reject the use of atomic weapons and negotiate an
end to World War II, allowing the Japanese to surrender and their emperor to become part of the postwar government.
© Teachers’ Curriculum Institute
S t u d e n t
H a n d o u t
1 4 A
Decision C: Whether Truman Made the Right Decision
Immediately after the United States dropped the atomic
bombs on Japan, the majority of Americans felt that the
right decision had been made. Surveys conducted by
Fortune magazine in the fall of 1945 revealed that more
than 50 percent of Americans believed the United States
“should have used the two bombs on cities just as we
did.” Another 22.7 percent felt the United States “should
have quickly used many more [bombs] before Japan had
the chance to surrender.”
Many U.S. soldiers supported Truman’s decision
as well. One young soldier stated, “When the bombs
were dropped and news began to circulate that [the invasion of Japan] would not, after all, take place, that we
would not be obliged to run up the beaches near Tokyo
assault-firing while being mortared and shelled . . . we
cried with relief and joy. We were going to live. We were
going to grow up to adulthood after all.”
Many officials in the top ranks of the military and
the government supported Truman’s decision to drop the
bombs. However, others expressed doubts. Admiral William D. Leahy stated, “It is my opinion that the use of
this barbarous weapon at Hiroshima and Nagasaki was
of no material assistance in our war against Japan. The
Japanese were already defeated and ready to surrender
because of the effective sea blockade and the successful
bombing with conventional weapons. . . . My own feeling was that in being the first to use [the atomic bomb],
we had adopted an ethical standard common to the
barbarians of the Dark Ages.”
Dwight D. Eisenhower, a general with enormous
prestige who would become the next president, maintained the reaction he had had to the first testing of the
atomic bomb. At that time, he had expressed the hope
that the United States would never have to use such a
weapon. Eisenhower continued to dislike seeing the
© Teachers’ Curriculum Institute
country, as he put it, “initiate the use of anything [so]
horrible and destructive.”
Some historians have severely criticized Truman’s
decision, arguing that in August 1945 the Japanese were
already defeated. They believe that the atomic bombs
were used primarily as a warning to the Soviet Union.
Although the two nations were allies during World War
II, the United States and the Soviet Union held very
different visions of the postwar world. The Soviets
wanted to maintain control over Eastern Europe. The
United States, on the other hand, wanted the Soviets to
allow Eastern European countries to become independent.
Historians critical of Truman’s decision argue that
his main reason for authorizing the use of the atomic
bombs was to scare the Soviets out of Eastern Europe
and away from Asia. These historians believe that, in
essence, the United States sacrificed the citizens of
Hiroshima and Nagasaki in a high-stakes poker game
between the two superpowers. Other historians counter
that it was the military pressures Truman faced at the
close of World War II that played the most important
role in his decision.
Critical Thinking Question C
Truman’s decision to use atomic weapons against Japan
is one of the most controversial choices made in history.
In retrospect, do you think that Truman made the right
decision when he authorized the use of atomic
weapons? Be prepared to defend your answer.
a. Truman did not make the right decision when he
authorized the use of atomic weapons
b. Truman made the right decision when he authorized
the use of atomic weapons.
Assessing the Decision to Build and Use the Atomic Bomb
23