The atom bomb: on the 70th anniversary of Hiroshima and Nagasaki, a look at the long shadow of nuclear war

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Date: Mar. 16, 2015
From: New York Times Upfront(Vol. 147, Issue 10)
Publisher: Scholastic, Inc.
Document Type: Article
Length: 3,755 words
Lexile Measure: 1360L

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On Aug. 6, 1945, 8-year-old Shigeaki Mori was walking across a bridge on his way to summer classes when "suddenly, I felt a massive shock wave and a blast from above," he recalled recently. That blast, which obliterated Mori's hometown of Hiroshima, Japan, was caused by the world's first-ever nuclear attack.

Mori was blown off the bridge and into a shallow river. When he regained consciousness, nearly everything around him was enveloped in thick black smoke, and the few things Mori could see, like a woman walking toward him, were horrifying.

"She was swaying ... and holding something white," he said. "I realized she was holding the contents of her stomach. " The United States dropped an atomic bomb on Hiroshima--and three days later on the Japanese city of Nagasaki--70 years ago to force Japan to surrender and end World War II (1939-45). The bombings killed as many as 250,000 and led to Japan's official surrender three weeks later, which arguably saved many thousands of American lives.

But dropping those bombs also had long-lasting consequences for the U.S. and the world that plague us today. In the years since, more nations have developed their own nuclear arsenals. Today, the threat of an attack by rogue nations like North Korea or Iran--or from a terrorist group that gets its hands on a bomb--remains a terrifying security problem for the U.S. and the world, with no easy solution.

Einstein's Letter

How did the U.S. come to possess the most destructive weapon the world had ever known? It started with a letter that physicist Albert Einstein wrote to President Franklin D. Roosevelt on Aug. 2, 1939--a month before Nazi Germany invaded Poland and started the Second World War. Einstein, a Jew who had fled Germany in 1933, warned Roosevelt about the potential destructive power of a nuclear weapon. He urged the president to fund a project to develop an atomic bomb--and quickly, before Germany's dictator Adolf Hitler beat him to it.

Roosevelt heeded Einstein's warning and partnered with Britain and Canada to recruit thousands of scientists to collaborate on the Manhattan Project (so named because it began in an obscure office in New York City). Stationed at isolated sites in Tennessee, Washington State, and New Mexico beginning in 1942, the scientists worked feverishly to figure out how to unleash the enormous amounts of energy contained in atoms. Einstein had first theorized the relation between matter and energy in his 1905 equation E = mc2 (see Timeline, p. 20). Because other countries, like the Soviet Union, Germany, and Japan, were also racing to develop an atomic weapon, the Manhattan Project was kept top secret.

Roosevelt never got to see the project's completion. He died on April 12, 1945. Shortly after, Secretary of War Henry Stimson sent President Harry S. Truman a brief memo referring to "a highly secret matter" that "has such a bearing on our present foreign relations ... that I think you ought to know about it without much further delay." (Truman had become vice president in January 1945, but Roosevelt had never told him about the Manhattan Project.)

The first test to see whether the bomb worked took place on July 16, 1945, with scientists and military experts gathering at Alamogordo, New Mexico. Just before dawn, a giant fireball exploded into a mass of dust and gaseous iron, soaring a mile a minute and forming a mushroom cloud. The blast carved a 1,200-foot crater in the desert floor. The blinding light and enormous roar traveled hundreds of miles.

The atom bomb came too late to affect the war in Europe, where more than 300,000 American soldiers had died; Germany had already surrendered in May. But fighting still raged in the Pacific, and Japan--which drew the U.S. into World War II by attacking Pearl Harbor in Hawaii on Dec. 7,1941--showed no signs of giving up. Dropping the atomic bomb as opposed to committing U.S. troops to an invasion of mainland Japan would save half a million lives, Truman said. America's use of the atom bomb--to this day, the only time it was ever used--is still controversial (see Debate, p. 22).

"The Americans had concluded that the Japanese, [with] their kamikaze suicide attacks and their refusal to surrender--you couldn't fight people like that with anything but full measures," says Christopher Hamner, a history professor at George Mason University in Fairfax, Virginia.

On August 6, an atomic bomb-named Little Boy by one of the nuclear physicists--was dropped on Hiroshima, a city of several hundred thousand people in southern Japan. Nearly 70 percent of the city's buildings and houses were leveled or irreparably damaged. The War Department (today the Defense Department) said the bomb packed more explosive power than 20,000 tons of TNT.

"The force from which the sun draws its power has been loosed against those who brought war to the Far East," Truman declared.

Three days later, a second bomb, called Fat Man, was dropped on Nagasaki, about 200 miles southwest (see map, p. 19). The two bombs killed between 150,000 and 250,000 people--some immediately and some from radiation sickness later on.

On August 15, Japan accepted the Allies' peace terms, and on September 2, it formally surrendered, finally ending World War II.

The Cold War

After the war, America found itself embroiled in a new conflict that would last five decades: the Cold War with the Communist Soviet Union, which had been an ally in the fight against Nazi Germany in World War II. The U.S. assumed it would have the upper hand in this battle because it was the only country in the world with atomic weapons. But America's nuclear monopoly abruptly ended in September 1949, when it became clear that the Soviets had developed their own bomb, helped in part by information from American spies Ethel and Julius Rosenberg.

The nuclear arms race between the U.S. and the Soviets was fierce. The irony was that both sides were extremely hesitant to use any of their bombs: They realized an attack from either side would result in immediate retaliation. That belief became known as "mutually assured destruction" (or the appropriately named acronym MAD). In schools across the U.S., students participated in "duck and cover" drills, practicing huddling under their desks in case of an attack. (Never mind that ducking under a desk in the face of a nuclear attack is pretty useless.) And the Cold War almost turned hot in 1962 with the Cuban Missile Crisis, which brought the U.S. and Soviets to the brink of nuclear war. (See Upfront, Sept. 17, 2012.)

To reduce the chances of a nuclear Armageddon, dozens of countries signed the United Nations' 1968 Non-Proliferation Treaty. And in the decades leading up to the Soviet Union's collapse in 1991, the Soviets and the U.S. signed several treaties to reduce their respective nuclear arsenals. (In recent years, the U.S. and Russia, which controls the old Soviet arsenal, have further reduced their stockpiles.)

Despite these efforts, the nuclear threat remains. Today, at least nine countries, including the U.S., have the bomb (see "The Nuclear Club"). And Iran is suspected of being close to developing nuclear weapons, posing a serious threat to Israel and Saudi Arabia--both longtime U.S. allies in the region--and most of Europe. The U.S. and its allies have imposed economic sanctions on Iran and have tried negotiating with its leaders to end its nuclear program, so far without success.

North Korea, which joined the nuclear club in 2006, is now led by the mysterious and unpredictable Kim Jong-Un. There's fear that he'll use his nuclear weapons to attack South Korea or Japan, or sell them to terrorist groups like A1 Qaeda or ISIS, which could target the U.S. Speaking at a nuclear-security summit in Belgium last year, President Obama said one of his biggest concerns is "the prospect of a nuclear weapon going off in Manhattan." The massive destruction that one terrorist could unleash--even without a military force behind him--is perhaps the most frightening legacy of the creation of the atom bomb.

"[Before 1945], if you wanted to do that kind of damage, you had to field an army of 75,000 men," says Hamner, the history professor. "Today, a very determined small group of people can do an incredibly disproportionate amount of damage."

With reporting by Reuters and Sam Roberts of The New York Times.


1905 E=[mc.sup.2]

Albert Einstein (above) publishes modern science's most famous equation: E=[mc.sup.2]. It says that vast amounts of energy can be unleashed from tiny amounts of matter. It's the basis for the development of nuclear weapons.


The Manhattan Project

Thousands of scientists are recruited to work on a top-secret effort to develop an atomic bomb for the U.S. during World War II. Three years later, they successfully test the bomb in the New Mexico desert.

1945 Hiroshima and Nagasaki


Soviet Bomb

A U.S. spy plane learns that the Soviet Union has tested an atomic bomb. Schools begin conducting "duck and cover" drills (above) in case of a Soviet nuclear attack.


Homegrown Spies

Americans Julius and Ethel Rosenberg are convicted of conspiring to steal designs for America's atomic bomb and deliver them to the Soviet Union. They are executed two years later.


Cuban Missile Crisis

U.S. spy planes discover Soviet-built nuclear missile sites in Cuba, just 90 miles from Florida. After a tense 13-day standoff with the U.S., the Soviets agree to remove the missiles.


U.N. Treaty

The U.N. approves the Non-Proliferation Treaty to halt the spread of nuclear arms. Nuclear nations agree to help other countries use the technology for peaceful purposes, like electricity. The treaty has been signed by 189 countries.



The Strategic Arms Limitation Treaty (SALT) between the U.S. and the Soviet Union in 1969 is the first of several agreements over the next two decades to reduce nuclear arsenals.


'New Start'

President Obama, who vowed to make nuclear disarmament an administration priority, signs a major arms-reduction agreement with Russia, called New Start. Obama has since pushed for further reductions, but Russian President Vladimir Putin has resisted.


North Korea & Iran

The U.S. fears North Korea could sell nuclear arms to terrorists who could target the U.S. The U.S. and its allies have imposed economic sanctions on Iran to curb its suspected nuclear weapons program; ongoing talks with Iran have so far yielded no progress.

The Nuclear Club

Who's got nukes, and when did they get them?

            UNITED             RUSSIA
COUNTRY     STATES   (formerly the Soviet Union)   U.K.   FRANCE

YEAR         1945               1949               1952    1960

ESTIMATED   7,315               8,000              225     300


YEAR        1964     1967     1974      1998     2006

ESTIMATED    250    80-100   90-110   100-120     <10


NOTE: India, Israel, and Pakistan haven't signed the
Non-Proliferation Treaty. North Korea did but later withdrew. Israel
has never admitted having nuclear weapons.


Lexile level: 1280L

Lower Lexile level (available online): 1080L

The Atom Bomb

On the 70th anniversary of the nuclear attacks on Hiroshima and Nagasaki, Times Past explores what led the U.S. to drop the atom bombs and why that decision is still controversial today.

Before Reading

1 List Vocabulary: Share with students the challenging general and domain-specific vocabulary for this article. Encourage them to use context to infer meanings as they read and to later verify those inferences by consulting a dictionary. Distribute or project the Word Watch activity to guide students through this process, if desired.

2 Engage: Watch the video on the Manhattan Project and discuss what motivated the nuclear scientists.







Analyze the Article

3 Road and Discuss: Have students read the article. Discuss what makes this a secondary source. (It was written in contemporary times by an author who researched the topic but didn't experience the events firsthand.) Then pose the following critical-thinking questions:

* Why do you think Albert Einstein felt compelled to reach out to President Franklin D. Roosevelt about the prospect of an atomic weapon in 1939? (Einstein knew that the enormous amount of energy inside atoms could be unleashed to create a powerful weapon, and he was concerned that German dictator Adolf Hitler would develop an atomic bomb before the U.S.)

* Explain why the Manhattan Project was kept top-secret. Do you think that such a large-scale government project could be kept under wraps today?

(Other nations, including the Soviet Union, Germany, and Japan, were also trying to develop atomic weapons--and the U.S. was determined to be first. Answers will vary on whether such a project could remain secret today.)

* Describe how the concept of "mutually assured destruction" (MAD) shaped the nuclear arms race.

(MAD was the idea that a nuclear attack by either the U.S. or the Soviet Union would result in immediate retaliation by the other side. Knowing this made both nations reluctant to use atomic weapons even as they stockpiled them.)

* Analyze why the U.S. is particularly concerned about North Korea's possession of nuclear weapons.

(North Korea's leader, Kim Jong-Un, is mysterious and unpredictable. There are concerns that he might use the weapons to bomb Japan or South Korea, both U.S. allies, and that he may sell the weapons to terrorists.)

4 Integrate the Primary Source: Project or distribute the pdf 'New Means of Destruction' (p. 13 of this Teacher's Guide), which features an excerpt from a petition discouraging the use of the atomic bomb written by scientists to President Harry S. Truman in 1945. Discuss what makes it a primary source. (Scientists wrote it in 1945.) Have students read the excerpt and answer these questions (which appear on the PDF without answers). Discuss. 1

* How would you sum up the scientists' purpose in petitioning the president? (The scientists' purpose is to ask the president to weigh all of the moral considerations related to using the atomic bomb and to appeal to him to use the bomb against Japan only as a last resort.)

* How would you describe the tone of the petition? (The scientists' tone may be described as straightforward or urgent. It is also respectful to the president.)

* Under what circumstances do the writers say that use of the atomic bomb against Japan might be justified?

(The scientists believe that the use of atomic bombs against Japan could be justified only under three conditions: if the U.S. first gave Japan a chance to surrender, making public the terms Japan would face; if Japan subsequently refused to surrender; and if the president weighed the moral implications of such a bombing, including the possibility that rival powers would come to possess nuclear bombs.)

* What "solemn responsibility" does the U.S. bear, according to the scientists? Why? (Because the U.S. had a "lead in the field of atomic power" as the only nation with an atomic bomb, the scientists argue that the country has a responsibility to prevent the uncontrolled acquisition of nuclear weapons by rival powers--a situation that would put cities in the U.S. and around the world in danger of annihilation.)

* What does the petition add to your understanding of the bombing of Hiroshima and Nagasaki as outlined in the Upfront article? (The article describes how the U.S. acquired the atomic bomb, how it decided to use the bomb against Japan, and what the legacy of that decision has been. The petition helps readers understand that there were concerns about using the bomb before the decision was made and that some people foresaw the possibility of a dangerous arms race.)

Extend & Assess

5 Writing Prompt

In what ways are we still living with the legacy of the creation of the atomic bomb? Write a brief essay, using evidence from both the article and the scientists' petition to support your response.

6 Classroom Debate

Choose a side: Was use of the atomic bomb inevitable once the technology existed?

7 Quiz & Paired Text

Use the quiz on page 10 of this Teacher's Guide. Try pairing the article with the book Hiroshima by John Hersey (true stories of six Hiroshima survivors). Compare and contrast how the two texts portray the consequences of the bombing.

Additional Resources

Print or project:

* Word Watch (vocabulary)

* 'New Means of Destruction' (also on p. 13 of this Teacher's Guide)

* Article Quiz (also on p. 10 of this Teacher's Guide)

* Analyze the Photo (also on p. 14 of this Teacher's Guide)

Video: The Manhattan Project


Choose the best answer for each of the following questions.

1. Who wrote a letter to President Franklin D. Roosevelt In 1939 that urged him to fund a project to develop

a nuclear weapon?

a Henry Stimson

b Albert Einstein

c Adolf Hitler

d Winston Churchill

2. The goal of the Manhattan Project was to

a replicate the earliest atom bombs that had been built in Nazi Germany.

b find a way to unleash the energy contained in atoms,

c covertly develop nuclear weapons without the knowledge of President Franklin D. Roosevelt,

d spy on several nuclear missile sites in Cuba.

3. The U.S. used atom bombs against Hiroshima and Nagasaki primarily to

a avoid a land invasion that would cost American lives.

b prevent an imminent second attack on Pearl Harbor.

c intimidate the Soviet Union.

d test the effectiveness of the new nuclear technology.


4. America's monopoly on nuclear weapons ended

a in 1969, when Japan developed an atom bomb.

b in 1960, when North Korea created a warhead it nicknamed "Little Boy."

c in 1954, when Britain purchased two American nuclear warheads.

d in 1949, when the Soviet Union developed an atom bomb.

5. Which country is suspected of being close to developing nuclear weapons today?

a North Korea

b South Korea

c China

d Iran

6. Which is true of the nuclear threat today?

a Every country has signed the United Nations' Non-Proliferation Treaty.

b At least nine countries have atomic bombs.

c The U.S. and Russia continue to increase their stockpiles of nuclear bombs.

d all of the above

7. What is "mutually assured destruction," or MAD, and what was its significance during the Cold War?--

8. Why do you think America's use of the atom bomb in World War II remains so controversial?--


1. [b] Albert Einstein

2. [b] find a way to unleash the energy contained in atoms.

3. [a] avoid a land invasion that would cost American lives.

4. [d] in 1949, when the Soviet Union developed an atom bomb.

5. [d] Iran

6. [b] At least nine countries have atomic bombs.


'New Means of Destruction'

Beginning in 1942, thousands of scientists collaborated to build the world's first atomic bombs as part of the United States government's top-secret Manhattan Project. By 1945, they had succeeded--and realized that use of the bombs against Japan could be imminent. Below is an excerpt from a petition drafted by 70 Manhattan Project scientists to President Harry S. Truman in July 1945. Read it along with the Upfront article about the atomic bomb. Then answer the questions below.

Petition to President Henry S. Truman, July 17, 1945

We, the undersigned scientists, have been working in the field of atomic power. Until recently, we have had to fear that the United States might be attacked by atomic bombs during this war and that her only defense might lie in a counterattack by the same means. Today, with the defeat of Germany, this danger is averted and we feel impelled to say what follows:

The war has to be brought speedily to a successful conclusion, and attacks by atomic bombs may very well be an effective method of warfare. We feel, however, that such attacks on Japan could not be justified, at least not unless the terms which will be imposed after the war on Japan were made public in detail and Japan were given an opportunity to surrender.

If such public announcement gave assurance to the Japanese that they could look forward to a life devoted to peaceful pursuits in their homeland and if Japan still refused to surrender our nation might then, in certain circumstances, find itself forced to resort to the use of atomic bombs. Such a step, however, ought not to be made at any time without seriously considering the moral responsibilities which are involved.

The development of atomic power will provide the nations with new means of destruction. The atomic bombs at our disposal represent only the first step in this direction, and there is almost no limit to the destructive power which will become available in the course of their future development. Thus a nation which sets the precedent of using these newly liberated forces of nature for purposes of destruction may have to bear the responsibility of opening the door to an era of devastation on an unimaginable scale.

If after this war a situation is allowed to develop in the world which permits rival powers to be in uncontrolled possession of these new means of destruction, the cities of the United States as well as the cities of other nations will be in continuous danger of sudden annihilation. All the resources of the United States, moral and material, may have to be mobilized to prevent the advent of such a world situation. Its prevention is at present the solemn responsibility of the United States--singled out by virtue of her lead in the field of atomic power....

In view of the foregoing, we, the undersigned, respectfully petition: first, that you exercise your power as Commander-in-Chief, to rule that the United States shall not resort to the use of atomic bombs in this war unless the terms which will be imposed upon Japan have been made public in detail and Japan knowing these terms has refused to surrender; second, that in such an event the question whether or not to use atomic bombs be decided by you in light of the considerations presented in this petition as well as all the other moral responsibilities which are involved.


1. How would you sum up the scientists' purpose in petitioning the president?

2. How would you describe the tone of the petition?

3. Under what circumstances do the writers say that use of the atomic bomb against Japan might be justified?

4. What "solemn responsibility" does the U.S. bear, according to the scientists? Why?

5. What does the petition add to your understanding of the bombing of Hiroshima and Nagasaki as outlined in the Upfront article?


Analyze the Photo

(See p. 19 in the magazine.)

1. What details do you notice in this photo of Hiroshima after the atomic bombing?

2. What words would you use to describe the image? Why?

3. How do you think the world might have responded to images like this one in 1945?


Explain how this photo adds to your understanding of the debate about America's use of the atom bomb against Japan.

Source Citation

Source Citation   

Gale Document Number: GALE|A405482311