Original subtitles

May, 1945.

The hot New Mexico desert

seemed far from the ravages of war in Europe.

100 tons of TNT.

A rehearsal,

to scale and calibrate the power of an untested atomic weapon.

Two months from this day,

Man would unleash the destructive power of a demon locked within

the very fabric of matter,

and plunge the world in the Atomic Age.

For the next 20 years,

testing the power of the atomic bomb

would hold the world captive by events shrouded in secrecy.

Events set into motion seven years earlier.

March, 1938.

Hitler invades Austria.

The Third Reich begins to flex its military muscle.

Later that year, German scientists

discover fission of the uranium nucleus

bringing the Third Reich one step closer to

discovering the secret of the atomic bomb.

Fear of German research

stimulated activity in the United States and England.

Fear that German scientists

could produce weapons of great devastation.

In the fall of 1939, Dr. Albert Einstein

wrote his now-famous letter to President Roosevelt,

explaining the urgency of work on uranium fission.

Roosevelt, a man of action, moved swiftly.

An advisory committee on uranium was appointed.

German forces invade Poland,

plunging the nations of Europe into a second World War.

A new branch of the Army's Corps of Engineers was established to administer work

on military uses of uranium.

Major General Leslie R. Groves, the man in responsible for the Pentagon,

was placed in charge of the project.

On December 2, the first self-sustaining chain-reacting pile

was successfully operated by Enrico Fermi.

Fermi's success brought intense efforts

between government and the private sector,

creating huge industries for uranium separation

in the town of Oakridge, Tennessee,

and for the production of plutonium in Hanford, Washington

at the shores of the mighty Columbia River.

This tremendous effort forged the materials necessary

for creating an atomic bomb.

The first atomic bomb was assembled at Los Alamos,

a secret laboratory in New Mexico.

When Dr. J.R. Oppenheimer arrived to take charge,

he began to surround himself with a galaxy of outstanding scientific stars.

From Los Alamos came the bomb design, and treatment of

many theoretical problems.

Yet many questions still remain unanswered.

What are the secrets of this new source of power and destruction?

Knowledge and information on all aspects of this new weapon

are essential,

and can only be discovered by further testing.

I had a very good friend, a Hungarian 10 years older than I, Le� Szil�rd.

He had a very independent mind,

and a great feeling what is coming.

He saw years ahead

that nuclear explosives would become important.

He was a friend, and I helped him.

For instance, I drove him to an important interview with Einstein

where Einstein wrote the famous letter to Roosevelt.

That started things going.

I myself was interested in theoretical physics,

in explaining atoms, molecular vibrations, knowledge, and more knowledge.

I didn't want to do it. But then...

Hitler not only swallowed up half of Poland,

he invaded the West.

And two days later, there was an invitation to a Pan-American Congress

where Roosevelt, whom I had never seen before, was going to speak.

And he made a remarkable speech,

how the world is really endangered by Hitler.

Among other things, and at the climax, he said:

"You scientists are blamed for the weapons to be used.

But I tell you,

that if you now won't work on weapons, the freedom of the world will be lost."

Now, you know, I had the feeling that Roosevelt was talking to me.

I was there when the letter was signed

that awoke his interest in nuclear energy.

I thought I knew he was talking about nuclear energy.

Of the 2,000 scientists there, I felt he was talking to me.

Of course, not true,

but in that twenty-minutes' talk,

my mind was made up.

I continued to like better to work on pure science,

but this had to be done.

And as long as it had to be done,

and I could contribute, I did,

and was never sorry for having done it.

The uranium-gun weapon, or "Little Boy" bomb,

was a simple design,

and scientists were confident it would work without testing.

The "Fat Man," or implosion bomb, was a more efficient design,

using plutonium instead of uranium.

Inside the very center of the bomb was an initiator

surrounded by a sphere of plutonium.

This sphere was encased

within a set of symetrically-located, high-explosive lenses

creating an implosion which forced the plutonium

into itself, attaining critical mass.

The blast instantly raised temperatures to 10 million degrees,

releasing a force of a million pounds of pressure,

vaporizing the tower and all desert life within half a mile.

The intensity of light was sufficient

to cause temporary blindness to an observer ten miles away.

With a yield 200 times greater than the hundred-ton test,

the fireball created a crater nearly one half-mile across,

And fused the desert sand into a green glass

still containing traces of radioactivity fifty years later.

Pearl Harbor plunged the United States into war.

For three years, gathering momentum with each small victory,

our forces had conducted an offensive

against the war-bloated Empire of the Rising Sun.

Slowly, island by island, mile by mile,

and then, with ever-quickening sweeps, the combined land, sea, and air forces of the Allies

drove against the borders of that empire,

forcing it back, until late in 1945,

only the bastions of the Japanese home islands remained to be stormed.

Ahead lay the greatest campaign of all:

invasion of Japanese homeland, and close-in, desperate fighting.

That this fanatical enemy would not quit until her last fighting man

had been driven from his cave and killed

had been established time and again by bitter experience.

The uranium-gun weapon, or "Little Boy" bomb,

was detonated over Hiroshima at an altitude of 1,800 feet,

the height to achieve maximum blast effect.

Three days later, the "Fat Man" implosion bomb

was detonated over Nagasaki.

In Hiroshima, 70,000 people were killed or listed as missing.

Of its 90,000 buildings, over 60,000 were demolished.

The implosion bomb dropped on Nagasaki took the lives of 42,000 people,

and injured 40,000 more.

It destroyed 39% of all the buildings in the city.

With a yield of 20 kilotons, similar to that of Trinity,

this weapon would be considered a nominal atomic bomb,

and provide a blueprint for all future nuclear weapons.

But the principal targets are naval ships.

We are seeking primarily to learn

What types of ships, tactical formations, and strategic dispositions

of our own naval forces will best survive

attacks by atomic weapons, should we ever have to face them.

Eleven months after the bombing of Hiroshima and Nagasaki,

Operation Crossroads was conducted at Bikini Atoll,

2,500 miles west of Hawaii.

The purpose of Crossroads

was to test the effects of atomic weapons using two devices,

similar in design to Trinity and Nagasaki,

Code-named Able and Baker.

Shot Able to be dropped from a B-29,

while Shot Baker would be detonated 90 feet below the surface of the water.

The target armada consisted of 185

Japanese, German, and American ships,

ranging from small amphibious craft to battleships and aircraft carriers.

The bomb will not start a chain reaction in the water,

converting it all to gas,

and letting all the ships on all the oceans drop down to the bottom.

It will not blow out the bottom of the sea

and let all the water run down the hole.

It will not destroy gravity.

I am not an "atomic playboy," as one of my critics labelled me,

exploding these bombs to satisfy my personal whim.

Animals, plant life, even biological warfare agents were assembled

to study the effects of heat, blast, and radiation.

The bomb missed its intended target by nearly 800 yards.

The blast sent five ships, including two destroyers,

to the bottom of Bikini lagoon.

All ships within a half a mile of the blast were heavily damaged.

But the damage was nowhere near that created by the following

underwater blast, known as Shot Baker.

Five, four, three, two, one... Fire.

Bikini Baker was an underwater burst of the same device,

and it produced much more damage to the armada of seventy ships.

For instance, the USS Saratoga

had the bottom of it essentially knocked out of it from the underwater burst.

The Saratoga sank and sets upright at the bottom of the Bikini lagoon at the present time.

I've often flown over Bikini lagoon, and on clear days, when the water is quiet,

you can still see the Saratoga setting there.

The area surrounding Shot Baker

had become seriously radioactive,

and could not be safely approached for some time.

This effect was not anticipated,

and ultimately led to a decision by President Truman

to call off a third deep underwater test, code-named Charlie.

This is the mile-high city of Los Alamos,

The Atomic City.

This is a modern pueblo, created by the people of the United States

as a research and development center for atomic weapons.

Since Eniwetok is a distant and primitive area,

men have to leave their stateside laboratories and homes

for a period running into months.

Since 1943, when Los Alamos was established,

men from this mesa have left the continental limits of the United States

to test the weapons they have created.

Two years after Crossroads,

authority was given by President Truman

to proceed with Operation Sandstone.

While the purpose of Crossroads

had been to test the effects of atomic weapons,

Sandstone's objective was to test new weapon designs.

Planning for such weapons had begun many years earlier,

when the scientists on Trinity

had developed other experimental designs for atomic weapons,

but were unsure of their success.

A joint task force was created to head out once again to the Pacific,

and procure the islands of Eniwetok, 200 miles west of Bikini,

where Crossroads had been staged.

In early November, the first construction crews arrived

to strip the islands of vegetation,

grade the land, and lay down tar and asphalt for roads.

Within six months, construction crews erected temporary housing

for many scientists and military personnel required for Sandstone.

Perched atop 200-foot steel towers,

the three devices utilized on Sandstone employed new technology

to double the explosive force of the bomb,

using the same amount of plutonium spent over Nagasaki.

This technology met Department of Defense requirements

for more efficient bombs

and increase the ability to stockpile nuclear weapons.

Remote-controlled tanks, guided by helicopter,

recovered fission samples near Ground Zero,

to measure the intense neutron and gamma radiation.

Radiochemical analysis of the pulverized coral sand

would yield secrets about the nuclear reaction,

and help in determining the efficiency of the new bomb designs.

The results of Sandstone affected the design of future nuclear weapons,

rendering the Mark III production components of the Fat Man bomb obsolete.

The Mark IV and Mark V designs

brought improved performance and a lighter weight to nuclear weapons.

Los Alamos National Laboratory Z Division

evolved into Sandia base,

located at Albuquerque, New Mexico's Kirtland Air Force Base.

Sandia's primary purpose was to engineer

and manufacture deliverable nuclear weapons, designed by Los Alamos.

In October of 1949,

Western Electric entered into a contract with the Atomic Energy Commission,

on a no-profit, no-fee basis to form the Sandia Corporation,

which assumed control of the base from Los Alamos.

Sandia brought assembly-line techniques

and mass production to nuclear weapons,

to build the nation's stockpile of tactical and strategic bombs.

Upon his return from Bikini, in public addresses,

in interviews, and in published articles, Admiral Blandy

made recommendations of grave import regarding the atomic bomb.

It is essential that no country gain ascendancy over the United States

in the development, manufacture, and tactical use of atomic weapons.

On August 29, 1949, the Russians detonated their first atomic bomb.

This event, coming five years earlier

than anyone in the West had predicted,

was largely the result of one man, Klaus Fuchs.

Fuchs, a Los Alamos physicist, had passed detailed blueprints

of the original Trinity design to the Russians.

With the emergence of the USSR as a nuclear rival in 1949,

the United States believed it had strong motivation

for intensifying its program of nuclear testing.

It was quite expensive and a lot of logistics involved

in carrying out an operation in the Pacific.

So in January 1951, the United States opened up the Nevada Proving Grounds,

which we now call the Nevada Test Site.

You know, this was about 60 miles north of Las Vegas.

To check out the weapons for Greenhouse,

Operation Ranger was conducted,

in which five new nuclear weapon types

were air-dropped at that new test site.

With the confidence of those new weapons in hand,

Operation Greenhouse proceeded in the Spring of 1951.

Four shots were conducted on Greenhouse.

One of the shots, Shot Easy,

was a Department of Defense structural effects test.

A 47-kiloton nuclear device on a tower was used,

and it loaded many, many of the structures that had been developed

for survivability in a nuclear weapons environment.

A fourth test on Operation Greenhouse was the Item test.

About a 45-and-a-half-kiloton test

in which tritium was burned in the very center of the nuclear explosion.

And this process of putting tritium at the very center of the nuclear weapon is called "boosting."

And we kicked the yield up from about 20 kilotons to 45 and a half kilotons,

more than doubling it by that process.

A very important feature in expanding the stockpile

of nuclear weapons of the United States at that time.

Another of the events on Greenhouse was the George event.

Now, George is a large, 225-kiloton weapon

that was used to burn a deuterium capsule.

And this is the first of our thermonuclear weapon experiments to ever be conducted.

Many people thought about it. We discussed it a lot.

At the end of the war, most people wanted to stop. I didn't.

Because here was more knowledge

in the coming uncertain period.

With a dangerous man like Stalin around

and our incomplete knowledge,

I felt that more knowledge is necessary.

Among the people who knew a great deal about the hydrogen bomb,

I was the only advocate of it.

And that is, I think, my contribution.

Not that I invented it. Others would have.

And others in the Soviet Union did.

But I was the one person who put knowledge,

and the availability of knowledge, above everything else.

And I must say it appears that that appealed to Truman,

and he made the right decision.

Welcome aboard the USS Estes.

As you may or may not know, the Estes, here, is the command ship

of Joint Task Force 132.

We have minutes to go before the first blast, Mike Shot,

of Operation Ivy.

59 minutes now, to be exact.

We've been here since daybreak.

Left Wetok last night, during the early morning hours.

Now, as you can imagine,

feeling is running pretty high about now,

And there's reason for it.

If everything goes according to plan,

we'll soon see the largest explosion

ever set off on the face of the Earth.

The test islands for Mike

are located at the top, or the northern sector, of Eniwetok Atoll,

some 25 miles from Parry and Eniwetok,

the two base islands of this atoll proving grounds.

Three islands making up the test site

were linked together by causeways.

These connecting roads were built to make it easy to get from island to island,

and to act as land platforms for some of the instrumentation.

Situated on the Zero island was the cab, or building, which housed the device.

The Mike device was known as a "wet bomb,"

because it used liquid hydrogen isotopes

to create the thermonuclear reaction.

This made the device very large,

weighing some 62 tons, and impractical to use as a deliverable weapon.

A plywood tube ran from the Zero island,

across the causeways, to a detection station

on the farthest island, a distance of nearly two miles.

This tube was filled with helium,

allowing lethal radioactive rays

faster travel to the detection station,

before the island was consumed by the fireball.

You have a grandstand seat here

to one of the most momentous events in the history of science.

In less than a minute you see the most powerful explosion

ever witnessed by human eyes.

The blast will come out of the horizon, just about there.

And this is the significance of the moment:

this is the first full-scale test of a hydrogen device.

If the reaction goes, we're in the Thermonuclear Era.

For the sake of all of us, and for the sake of our country,

I know that you join me in wishing this expedition well.

It is now 30 seconds to Zero Time.

Put on goggles or turn away.

Do not remove goggles or face burst

until ten seconds after the first light.

Minus 15 seconds.

Minus 10 seconds.

Niner, eight, seven, six, fiver...

four, three, two, one...

2-6 approaching Ground Zero,

coming up on Bogon.

The detection station on Bogon appears to be in good shape.

No visible sign of plywood tube.

All test islands seem to be swept clean.

Elugelab is completely gone.

Nothing there but water and what appears to be a deep crater.

In the spring of 1953, the Atomic Energy Commission

and the Department of Defense conducted eleven nuclear weapon tests in Nevada

under the code name Upshot-Knothole.

The objectives of Upshot-Knothole were to test new nuclear devices,

improve battlefield tactics,

and to study the needs of civil defense against a Soviet attack.

The first of the events, code-named Encore, was a 27-kiloton nuclear device

air-dropped and detonated at about 2,800 feet

above a large blast line.

The second Department of Defense burst, called Grable,

was detonated at the same general area,

and it was delivered by the Army�s new artillery cannon.

A 280mm projectile was fired and detonated over about the same blast area,

with a yield of about 15 kilotons, at an altitude of about 500 feet.

Now, the smaller yield, 15 kilotons at 500 feet,

produced a great deal more damage

than had the larger yield, Encore event, 27 kilotons at 2,800 feet.

And that's because the smaller yield at the lower altitude

produced a very abnormal waveform which we call a "precursor,"

which is very stong, dynamic winds

which, to drag-sensitive targets, produces extensive damage.

For instance, a Jeep at a given level on Encore may not have been damaged at all,

but on Grable, with a precursor loading,

that Jeep would be completely torn to pieces

and thrown down the blast line distances like 500 feet.

Well, there were many other peculiarities to those two shots,

but it opened up a whole new vista

of "how do you use nuclear weapons in a combat situation?"

Common sense tells you this is dangerous and foolish.

You wouldn't risk your neck in a trick like this.

Common sense tells us that being shot out of a cannon is dangerous business.

Common sense tells you not to be careless at an airfield

with propellers and jet engines in action.

Handling dynamite - this, too, looks dangerous.

But it's an everyday job for these men,

because they observe commonsense safety precautions.

But sometimes we forget that security violations

can be dangerous business, too.

If classified information about this test mission fell into enemy hands,

the consequences could be disastrous to all of us,

individually and collectively as a nation.

Security is only common sense.

Don't take chances.

Avoid loose talk.

Safeguard classified information.

Report security violations at once.

Prompt action may prevent a minor incident

from developing into a serious one.

Avoid writing about classified material in letters home.

Be sure you're secure! Don't be careless!

I hate a careless man!

Work on high-yield hydrogen bombs

had progressed from Operation Ivy,

culminating in the spring of 1954 with Castle Bravo:

the largest device ever detonated in atmospheric testing by the United States.

Bravo was a hydrogen bomb using solid thermonuclear fuel,

confirming the designs of Edward Teller and Stan Ulam,

and paving the way to producing aircraft-deliverable hydrogen bombs

and more effective weapons.

Significantly exceeding its expected yield by two and a half times,

Castle Bravo, with an explosive power of 15 megatons,

stripped islands clean of vegetation

and took the scientists by surprise.

The huge explosion released large quantities of radioactive debris

into the atmosphere.

This resulted in the exposure and contamination of some servicemen,

natives, and the crew of a Japanese fishing boat

which had gone unnoticed in the security zone around the blast.

This incident pushed the dangers of fallout

from nuclear weapons clearly into the public mind.

Let's face it:

the threat of hydrogen bomb warfare is the greatest danger

our nation has ever known.

Enemy jet bombers carrying nuclear weapons can sweep over a variety

of routes and drop bombs on any important target in the United States.

The threat of this destruction has affected our way of life

in every city, town, and village from coast to coast.

These are the signs of the times.

Only in practice now; a rehearsal, a training exercise.

But tomorrow, this siren may mean the real thing.

And if you hear it, as you drive in your auto,

as you sit in your office, or work at your bank,

wherever you are, what will you do?

What will happen to you?

Professor, let me tip your hat back so we can get a good view of you

as I ask a very personal question:

How old are you?

My next birthday, I'll be 65, sorry to say.

That makes you the oldest, and yet really the youngest,

from what we've observed here,

inhabitant of our trench, so close to Ground Zero.

Arthur, there's a charming lady right behind you.

Would you mind if we talked to her, too?

I'd like to get a little feminine reaction here, too.

This is Helen Leininger from New York City.

Helen, how long have you been waiting now?

Oh, about eight days.

- Eight... nine days... - Nine days, yes!

...if we do the calculation right.

Well, Grant, I guess we'd better get back up to Media Hill

and see what's going on, and how close to H-Hour we really are.

Well, here on Media Hill, Roy, the big story as far as we can determine from looking out there

is the Civil Defense story,

as well as that story of the military and the armored vehicles,

the tanks and the personnel carriers.

Now, Roy, once again, I want to call you in so we can take a look

at our split-screen arrangement that we have here,

not only our cameras here on Media Hill,

but the camera that you have down in the trench,

so come in on that split screen.

In just a few seconds now, you'll see me assume this position,

matter of fact, there's our cue now.

Everybody down, get down in the position

I'm going to shield my eyes against flying debris.

Pull my helmet down on the nape of my neck

so that we don't get too many flying rocks.

All right. Good luck, Roy. Now let me to explain something about this screen:

This screen, across the bottom of the section that I am,

will represent one mile on your camera. The top part, two miles.

We're going to switch to another camera, I'm going to move out of here...

Ten, nine, eight, seven, six,

five, four, three, two, one, zero.

The shock wave will arrive in the control point area in approximately half a minute.

Almost nine years had passed

since the cancellation of the deep underwater test

on Operation Crossroads.

That test was finally conducted as Operation Wigwam.

500 miles off the coast of San Diego, California,

a 30-kiloton nuclear device was suspended by a cable

2,000 feet below an unmanned barge.

A tow line, six miles long,

stretched from the barge.

Suspended from this tow line

were three unmanned submarines called "squaws."

Cameras and instruments were placed inside each sub

to record the effects of the nuclear detonation.

The purpose of this operation

was to determine the fatal range of an enemy submarine

to a deeply-detonated nuclear weapon.

25 seconds to Zero Time.

20 seconds to Zero Time.

15 seconds to Zero Time.

Ten, nine, eight, seven, six,

five, four, three, two, one...

Operation Redwing was conducted in the Pacific,

primarily to test high-yield thermonuclear devices.

Seven months prior to Redwing, the Soviet Union had demonstrated

the ability to deliver thermonuclear weapons

by strategic bombers,

tipping the balance of power in their favor.

The Cherokee event would be the first delivery by U.S. aircraft

of a thermonuclear weapon.

This weapon would detonate with a yield of three and a half megatons.

Almost 200 times the power the Trinity device.

Cratering from high-yield detonations

was taking its toll on the Pacific test islands.

Real estate at the Pacific proving grounds was disappearing,

and land was at a premium.

Barges were increasingly employed as a cheap form of transportation

to carry thermonuclear bombs out to sea for detonation.

Many of these tests would document an ever-growing concern.

One special phase of the study

concerned the amount of radiation that would pass through the human body.

This required instrumentaion in the stomach.

A small capsule was devised as a film stack,

with alternate bits of film and spacers.

Secured with a string and paraffin coated, the capsule is swallowed.

One end of the string hangs out of the mouth, so that the capsule can be retrieved

after exposure, and the radiation measured.

Gamma radiation may do its damage in either of two major ways,

or both:

One, it may physically and directly destroy tissue,

or eventually cause the development of some kind of cancers.

Those which concern us principally have life periods

ranging from several years to thousands of years.

They can do no harm, unless they are taken into our bodies

with food or drinking water, or in the air we breathe.

Let us consider the results of a powerful thermonuclear explosion

at the Pacific proving grounds in the Marshall Islands,

11 degrees north of the Equator.

The huge cloud soars up, punches through the tropopause,

and finally spreads and stabilizes as high as 70 or 80 thousand feet,

entirely within the stratosphere layer.

This brings us to the most widely discussed fission product, strontium-90.

Chemically similar to the soil calcium with which it becomes mixed,

the strontium-90 follows calcium through its regular cycles,

into our plant foods,

and into the bones, meat, and milk of our plant-eating animals.

Reaching our own bodies, the strontium-90, like calcium,

tends to be concentrated in our bones,

particularly those of children who are building new bone.

The radiation from strontium-90 has extremely short range in the body,

so it causes no genetic threat to the reproductive cells.

It does pose a threat to the bone marrow, and the bone itself,

in the form of either leukemia or bone cancer.

If this should happen, it would be a tragic thing for those injured, no matter how small the number.

Whether these statistically very few casualties can be justified

is a personal value judgment outside the scope of this report.

Each citizen must make his or her own evaluation.

There are those few who loudly maintain

that there is no actual threat to the free world at all,

certainly none that can justify either nuclear testing or nuclear armament.

The opposite viewpoint holds that the development of our nuclear power

has been an absolutely necessary protection

against Communist hostility and nuclear threats.

In this view, the fallout casualties, if any,

will be seen as those of unidentified soldiers

in the service of humanity,

unknown soldiers in a war which has not struck,

and which our nuclear power may indeed prevent from ever striking.

In the fall of 1957, with test moratoriums looming on the horizon,

24 nuclear tests were conducted in the Nevada desert,

under the code name Operation Plumbbob.

During Plumbbob, the Hood event would become the largest test

ever conducted in the atmosphere within the continental United States.

Hood, a 74-kiloton device,

was suspended 1,500 feet above the desert floor on a balloon.

While new weapon designs continued to be tested,

the Department of Defense used the series

to accelerate military training in nuclear warfare,

while continuing its study of the effects from nuclear explosions.

The 21st test conducted during Operation Plumbbob was "The Rainier Event."

This was the first fully-contained underground nuclear weapon detonation conducted by the United States.

The 3-kiloton device was detonated 790 feet below Rainier Mesa,

vaporizing rock into a molten bubble 100 feet wide.

This technology would have great importance after the Limited Test Ban Treaty,

which would prohibit all but underground testing of nuclear weapons,

and hide future experiments from prying eyes.

During Operation Hardtack, the United States detonated 35 nuclear devices,

as many as had been fired in all prior Pacific tests.

By now, nuclear weapon tests were perceived, in large part,

as saber-rattling,

increasing the international tensions

that could lead to all-out nuclear war.

Against mounting pressure,

the United States government still believed that the weapons were vital,

and were the only counterweight to offset superior Soviet manpower.

The Soviets, having just completed an elaborate series of atmospheric tests,

were now likely to make a move to renounce testing,

knowing full well that the U.S. was involved in a massive operation.

And operations were conducted at Eniwetok and Bikini, as we had before,

and a new operational site was brought in under Operation Hardtack,

And that was the Johnston Island operations.

During the tests, one of the events of some significance is the Cactus event.

This was a little 18-kiloton device that produced

a crater about 137 feet across and 37 feet deep.

Many years later, in 1980, all of the fission debris

and radioactive material on Eniwetok Atoll

was gathered up and dumped into the Cactus crater,

and then a concrete dome was placed over the crater

to keep and stabilize the radioactive material that had been contained in it.

A year before Hardtack,

the Soviets launched a small satellite named Sputnik 1.

Concerned by the superiority of Soviet rockets,

the United States conducted its first two missile-borne,

high altitude detonations,

known as Teak and Orange.

The nuclear weapons for Teak and Orange

were carried aloft into space by the Redstone missile,

developed by Wernher von Braun.

Von Braun and his crew had developed

the V-2 rocket for Germany during World War II.

The Redstone was considered an extension

of this World War II technology

and had a limited range.

Utilizing liquid oxygen for fuel,

The Redstone would propel its nuclear cargo into the Earth's upper atmosphere

and release it for detonation.

Teak, with a yield of 3.8 megatons,

detonated nearly 50 miles above the surface of the Earth.

The explosion created a violent magnetic disturbance in the atmosphere,

known as EMP, or Electromagnetic Pulse.

This phenomenon silenced radio transmissions for nearly eight hours,

and damaged electrical circuits from Hawaii to New Zealand.

Immediately following shots Teak and Orange in the Pacific

the United States conducted Operation Argus:

Three 1-kiloton missile-borne tests in the South Atlantic.

The Argus experiment sought to create and explore

trapped bomb radiation in the Earth's Van Allen belts.

Detonating 300 miles above the Earth,

the experiment sought to create a radioactive shield

to impede the performance of a Soviet missile attack.

These pictures, enlarged from 16mm for your theater screen,

are the first to show the hand-raising which makes history in Russia,

for it marks the approval by the Supreme Soviet

of Nikita Khrushchev's rise to the Premiership,

and power that was once Stalin's.

The free world awaits the obvious diplomatic thrusts,

the first coming barely four days later.

Russia announces it is suspending further nuclear tests,

a statement which the U.S. brands a propaganda maneuver.

The United States is prepared,

unless testing is resumed by the Soviet Union,

to withhold further testing, on its part, of atomic and hydrogen weapons

for a period of one year from the beginning of the negotiations.

For two years, an uneasy moratorium on weapon testing

continued between the United States and the Soviet Union.

Secretly, the Soviets began designing

new weapons of mass destruction,

including a 57-megaton hydrogen bomb,

the largest nuclear weapon ever built.

This monster bomb was a scaled-down version

of a 100-megaton design,

and was aircraft-deliverable.

As he said he would, Mr. Khrushchev has exploded his giant bomb,

in cynical disregard of the United Nations.

By this act, the Soviet Union had added injury to insult.

They broke the moratorium on nuclear weapons testing.

They have raised atmospheric pollution to new heights.

They have started a new race, for more deadly weapons.

They have spurned the humanitarian appeal of the United Nations

and of all peace-loving peoples.

They have advanced no solid justification

for exploding this monstrous and unnecessary weapon.

They have been wholly unmoved

by the dangers of radioactive fallout to the human race.

The United States delegation deeply deplores

this contempt for world opinion.

And we think that, in the light of this somber development,

other delegations may wish to express their views

on this shocking and distressing news.

For today, Mr. Chairman, the world has taken a great leap backward

toward anarchy and disaster.

The Russians had shattered the voluntary moratorium.

The United States would soon follow suit,

with an extensive series of weapon tests for massive retaliation.

Tensions mounted, as nearly 100 nuclear tests were conducted

between the Nevada test site and the Pacific Ocean,

under the code names Nougat, Storax, and Dominic.

Of primary importance were the uncertainties

of offensive and defensive weapons systems

in place, but unproven, since the beginning of the voluntary moratorium.

Operations resumed on Johnston Island and Christmas Island

during Operation Dominic.

The United States negotiated the use of Christmas Island from the British,

who had used the island to conduct their own thermonuclear tests.

Multi-megaton nuclear weapons were loaded aboard B-52 strategic bomber aircraft,

delivered from Hawaii, and air-dropped off the south end of Christmas Island.

The Department of Defense continued its advance into space

by conducting five high-altitude tests above Johnston Island.

Most of these bombs were carried aloft by the Air Force's Thor missile,

to continue the research

of neutralizing incoming enemy warheads high above the Earth.

Nuclear weapon testing had joined the space age.

This small step towards safety can be followed by others,

longer and less limited,

if also harder in the taking.

With our courage and understanding enlarged by this achievement,

let us press onward in quest of man's essential desire for peace.

As president of the United States, and with the advice and consent of the Senate,

I now sign the instruments of ratification of this treaty.

Tightrope was the last atmospheric test ever conducted by the United States.

And it was fired from Johnston Island

in the Nike-Hercules air defense missile

and detonated, again, well above Johnston Island.

And that ended this whole series of atmospheric testing by the United States,

when, in 1963 we entered the Limited Test Ban Treaty,

that prohibits any atmospheric testing.