Original subtitles

[narrator] On the eve of World War II,

Downloaded from YTS.MX

a scientific discovery

would change the stakes of war

Official YIFY movies site: YTS.MX

and the world forever.

Splitting the uranium atom,

the US, Germany, and Japan

each race to harness the power of the atom

before the enemy does.

What if Germany had gotten to the atomic bomb

before the United States did?

The race was a very real one.

[narrator] To succeed, each country would need

the brightest minds,

new technology,

and new science on a scale never seen before.

Secret shipments,

secret science, modern forensics.

Taken from Germany,

from nuclear reactor Hitler tried to build.

[narrator] And newly uncovered history.

Tell an epic World War II story

of Hitler's Secret Bomb.

[suspenseful music playing]

[suspenseful music playing]

Sit down, Herr Wohlthat.

[typewriter clacking]

When did you come to Japan?

[Helmuth speaking]

And why were you sent here?

[Helmuth speaking]

And what kind of goods?

[Helmuth speaking]

And you said trade,

what did Japanese want from Germany?

[Helmuth speaking]

Yes, go on.

[Helmuth speaking]

Uranium?

Germany was really the center of the physics community.

Everything was happening

at the Kaiser Wilhelm Institute for Physics.

Germany had some of the best scientific minds

for nuclear physics in the world.

It included of course Werner Heisenberg,

Otto Hahn.

Other physicists like Carl F. von Weiszacker.

And Germany was ready for an intense investigation

into nuclear fission.

In 1939, German scientists announced that

they had split the Uranium atom.

Unlike other atoms, this released tremendous

amounts of energy raising tantalizing possiblities

of a new fuel source.

The fact that you could split uranium came as, uh,

sort of a total surprise to the scientific community.

Never before as a single scientific discovery,

something you could do in a laboratory on a table.

Uh, it changed the course of nations,

it changed the course of history.

No longer any doubt about it.

That Uranium is splitting into at least two big parts.

Prior to 1939,

physicists thought that atoms

were sort of, like, a fortress,

that they were large, and strong, and powerful.

All it took to break apart a uranium atom

was one small neutron,

a very tiny, subatomic particle.

And in doing so, you would release

a huge amount of energy.

The actual discovery was done by scientists,

one working in Berlin, Otto Hahn, a chemist,

and he found very unusual results.

He sent it to his collaborator,

Lise Meitner.

[Dr. Hiebert] Lise Meitner had left Germany.

She was in Sweden.

She got a letter from Otto Hahn

who was her colleague over in Berlin.

They were bombarding uranium

and they were seeing this bizarre response

that they really couldn't figure out what was happening.

And since she talked it over with her nephew

who was also a physicist

and they were on a walk one day,

when all of a sudden, in the middle of the woods,

it just came to her what was happening.

And she sat down in the snow and wrote out

what we now understand to be fission.

[Dr. Wellerstein] And the consequences of this

would reverberate across not only World War II,

but throughout our modern world today.

The year was 1939,

and the world would never be the same.

[tense music playing]

The news of nuclear fission spread throughout

the global scientific community like wildfire.

This was something completely unexpected

and extremely exciting,

not just for its scientific properties,

but for its potential industrial

and maybe even military potential.

[narrator] By 1939,

the Nazis were making life difficult,

even dangerous for some of Germany's scientists.

[broadcaster] When Adolf Hitler became

absolute ruler of Germany,

his calculated and well-organized

oppression of racial and political minorities

has been steadily growing.

[Dr. Hiebert] As the Nazis began to take over,

it became increasingly apparent

that anyone with any Jewish background

is going to have to leave.

[broadcaster] Fleeing from Nazi Germany,

6,000 to America,

23,000 to Palestine.

There were a substantial number of refugee scientists

in the United States who had fled

the growing hostilities and racism in Europe,

including Albert Einstein,

Eugene Wigner,

Leo Szilard.

A cornucopia of talent

who had firsthand experience

with Germany and a fear of it.

[suspenseful music playing]

Many of the scientists who were interested in fission

originally were just interested in it

for its scientific possibilities.

The possibility of it being turned into a weapon

seemed like something very far on the horizon.

But there were a few who started to worry

about this very seriously, very early on.

At the most important of which

was probably Leo Szilard,

Hungarian refugee,

who had been thinking about the possibility

of releasing nuclear energy for many years.

Szilard had studied in Germany

and he was a good friend of Albert Einstein's.

He started thinking about how you could use,

uh, the new science of radioactivity

to release nuclear energy.

He concluded that if you could find

a reaction

that you could use in a chain reaction,

so that one reaction created multiple other reactions,

that you could release tremendous amounts of energy.

But he didn't have a reaction that worked for that

until the discovery of nuclear fission.

In 1939, when Szilard and Wigner

learned about nuclear fission,

they were both in the United States.

Szilard in particular was extremely agitated

about the possibility that the Germans might use,

uh, nuclear fission, uh, to create a wonder weapon.

So when Szilard heard about this,

he immediately understood

that you could use this for weapons.

And they wouldn't just be regular sorts of weapons

that had been used in war before,

they would be weapons that completely dwarfed

the entire output of all previous wars.

Wigner and Szilard decided that what they needed to do

is contact people,

that they needed to start things in motion

that might hinder Germany

or at least help beat them towards getting a bomb.

The first idea they had

was writing to the Queen of Belgium.

The Belgians had control over the Congo and Africa,

which was the richest source of uranium

on the entire planet.

And Szilard and Wigner wanted to make sure

that Belgian uranium

didn't end up in German hands.

Uh, in order to be taken seriously,

they decided that they would need to go

to someone they knew who had a lot

more scientific and public standing,

Albert Einstein.

They drove out to Einstein's

vacation house on Long Island,

and sat with him on the porch,

and talked with him about the issue.

Einstein immediately recognized

that this was important

once they laid it out in front of him.

They had several strategies for thinking about

how to make this happen,

whether it was writing to the Queen of Belgium,

uh, or to the Belgian Ambassador.

Ultimately, a few weeks later,

uh, Szilard went back to Einstein

and decided that the only real way

to get this taken to a higher level

was for Einstein to write a letter

to the President of the United States,

Franklin Roosevelt.

They worked on several drafts of the letter,

but the next question is, how do you get somebody

like Roosevelt to actually read this letter?

Because they feared that a man like Roosevelt

is just drowning in paperwork every day.

They decided to tap the services

of a friend of theirs, Alexander Sachs, an economist.

And they would use Sachs to personally present

Einstein's letter to the president,

but the earliest appointment

that Sachs could get with Roosevelt

was in October 1939.

In between, everything changed.

[broadcaster] War has struck again.

Poland was invaded September 1st, 1939,

which was the first in a series of successes

with the German blitzkrieg.

Blitzkrieg means lightning war,

and it's a strategy you pursue

when you have limited resources,

limited manpower.

You focus your troops,

you make them mobile,

in the hope that by concentrating

your forces in a few areas,

you can quickly break through the enemy lines,

encircle them, force them to surrender

before essentially you run out of materials.

Germany knocked off one country after the other.

After each victory, they then stripped

whatever they could from that country

to use in the next attack.

[tense music playing]

[narrator] Through the fall of 1939

and the summer of 1940,

the Nazi blitzkrieg rained terror across Europe,

taking one country after another.

The US had not yet entered the war,

and Hitler was confident

that he would not meet resistance from the USSR.

[Dr. Walker] Austria, Czechoslovakia,

Poland fell after about six weeks,

Denmark, and Norway,

Holland, Belgium and France,

by which time Hitler had reversed

the Treaty of Versailles,

and probably reached the peak of his popularity in Germany.

This was all planned in the sense

that Germany had been setting up alliances.

First with the Italy, in what came

to be called Axis Pact.

Then the Anti-Comintern with the Empire of Japan

that is aimed against the Soviet Union.

But most surprisingly, uh, just a few weeks

before the invasion of Poland...

[broadcaster] The war was set on its heels

by the announcement of a treaty

between the Russians and the Germans,

in which they agreed not to fight each other.

[Dr. Walker] These two ideological enemies

agreed not only not to attack each other,

but to very generous trade terms.

Germany was free

to invade Poland, because they had

an understanding with the Soviet Union.

They only invaded halfway,

the Soviet Union would then invade Poland

from the east and divide the country up.

[narrator] In the United States,

a policy of isolationism in place

since World War I was eroding.

While Japan's recent conquest in Asia

had been largely ignored,

the Nazi threat blazing across Europe

could not be.

[Dr. Wellerstein] Einstein's letter now

had a very real urgency to it.

In his conversation with Roosevelt,

Sachs laid out a future

in which nuclear energy could be used

for great peril or for great good.

You could use this potentially

for making machines

that would generate tremendous amount of power,

but you could also use it for making weapons

that would be on a scale hitherto uncontemplated.

And the letter laid out

a pretty unpleasant situation.

It explained that this research

had been taking place in Germany,

and that the Germans appeared to have been

seizing Czechoslovakia

areas that contained uranium ores.

And that they had extremely high-quality researchers

potentially working on this issue,

nuclear fission having been discovered in their country.

And it essentially pointed out

that in the United States,

they had very limited and poor uranium ores,

and they had no coordination whatsoever

between their scientists.

The letter suggested the government

ought to be paying attention to this.

Because if the Germans are working on it,

they might have a significant advantage

compared to the United States.

Roosevelt agreed

that something needed to be done.

He created a committee called the Uranium Committee.

Roosevelt wrote an immediate reply to Einstein,

thanking him for bringing this to his attention.

And from that moment onward,

the world was on a path towards the bomb.

[speaking in Japanese]

Even before World War II began,

Germany and Japan had united in a treaty,

the Anti-Comintern Pact

against international communism.

[speaking foreign language]

To hold the Soviets down in Asia.

[Dr. Grunden] Germany has one of the most

advanced militaries in the world.

Japan also has an advance military.

The Japanese army defeated the Russians in 1905,

and they had taken much of China.

Japan has a long tradition

of borrowing technology from abroad,

they're looking to modernize.

And when it came to the air forces

of the army and navy,

they went to Germany,

they went to the United States,

and they borrowed the most advance designs

that they could find.

[speaking Japanese]

In 1939,

the Japanese delegation returned to Japan

with some 250 German engineers

to help them build the aeronautics industry.

By 1941,

Japan has one of the most sophisticated airplanes

in the entire world.

The famous Zero.

The Zero was faster, more nimble,

and had a tighter turn ratio

than almost any other plane in the world.

[narrator] For the Japanese, the alliance with Germany

had helped improve their military.

For the Nazis, the alliance with Japan

had new importance,

resources needed to continue the war.

Japan including its large

expanding economic empire,

Malaysia, Vietnam, Korea, China,

now had a lot to offer Germany.

There were materials for the weapons of war themselves,

things like tin, tungsten,

tea, caffeine,

even opium as a painkiller.

Hermann Goring, the second man

in the Nazi State

and in charge of acquiring resources,

now began taking steps

to ensure the necessary materials for war.

[tense music playing]

[narrator] And it's Hermann Goring

who sends Helmuth Wohlthat to Japan.

[Dr. Walker] Wohlthat had fought in World War I

as a cavalry officer.

He had an American connection

studying in Columbia University.

When he returned to Germany

and began working for the Third Reich,

uh, in their foreign trade office.

[tense music playing]

[Dr. Walker] In the spring of 1941,

Wohlthat and his small team arrived in Japan

with 200 million Yen

and a list of vital supplies that Germany needed.

In return,

Germany sent Japan its materials needed

to fabricate weapons,

steel, glass,

lead, mercury.

Trade with Japan appeared vital.

Germany would need everything they could get a hold of

in order to fight the war.

[Helmuth speaking]

[narrator] And it was Wohlthat's job

to ship these vital goods back to Nazi war effort,

but one huge obstacle stood in his way.

[tense music playing]

[Dr. Grunden] December 7th, 1941,

the Japanese launched an attack on Pearl Harbor

from six aircraft carriers.

A total of three hundred and forty planes

launched in two waves of a hundred and seventy each.

Their goal, disable America's ability

to fight Japan's expansion in the South Pacific.

Of eight US battleships in port,

four were sunk

and the others heavily damaged,

also destroyed.

Three cruisers, three destroyers,

a minelayer, and a training ship.

Over 2,400 Americans dead.

Since the unprovoked

and dastardly attack by Japan,

a state of war has existed

between the United States

and the Japanese empire.

[crowd applauding]

Immediately,

all of the engines of American industry

and American government

pivoted towards the production for war.

Tanks, ships,

airplanes, rockets, you name it.

Anything that could be produce

to help the war effort,

and one of these was nuclear fission,

because the potential consequences

of losing a race for nuclear fission,

if it was possible, we're far too high to risk.

The United States had no specific knowledge

of what was going on in Germany or in Japan.

They didn't know

that they were working on nuclear fission,

but they felt that they had to assume that they were.

Despite Hitler,

German science was still considered

among the best in the world.

President Roosevelt and his scientific

and military advisors were afraid

that the Germans had a two-year ahead start

and would build the bomb first.

[broadcaster] To the scientists,

this dramatic news brought a great sense of urgency.

[dramatic music playing]

Japanese scientists were definitely keeping pace

with their colleagues in the West.

Just 10 months after the discovery of fission,

two Japanese scientists, Arakatsu Bunsaku

and Hagiwara Tokutaro

published their own paper

on the number of neutrons released in fission.

They predicted that a chain reaction was possible.

And by harnessing the power of the atom,

this could bring huge innovations

in motive power for ships,

for submarines, possibly even for bombers.

Both the army and navy became very interested

in harnessing the power of the atom

for military purposes.

But the question remained,

did they have enough resources?

Did they have enough uranium?

Did they have the ability to create a nuclear reactor

and more importantly, to create a super weapon?

The army project really gets started

when, by chance, Nishina Yoshio,

the premier physicist of Japan

meets General Yasuda on a commuter train in Tokyo.

And the two of them begin to have a conversation

about the war.

And Nishina mentions

that there are great developments

in physics, in nuclear physics,

and perhaps the army could do something

for the military.

Yasuda is excited about this prospect,

and thus, is born the army's foray

into nuclear research.

In the spring of 1941,

Nishina returns to the Riken Institute,

the most prestigious nuclear research facility

in all of Japan.

There, he employs 110 scientists

all engaged in various aspects of nuclear physics.

At the Riken, Nishina worked to complete

a new 60-inch cyclotron

for separating isotopes.

Hagiwara published yet another essay

titled "Super weapon U-235,"

indicating that they fully understood

the promise and potential of the U-235 isotope

for developing nuclear weapons.

But to have enough U-235

would require massive amounts of uranium ore.

[dramatic music playing]

For President Roosevelt and the United States,

the imperative was clear, they needed to build a bomb

before Germany and before Japan did.

They were convinced that they were in a race

to build the most powerful weapon ever created.

[broadcaster] Yellow ore shows good uranium,

while black ore is extremely rich

in fissionable material.

At $7 a pound, the uranium search rivals

the Old West's gold rush.

The biggest difficulty in making an atomic bomb

is getting the fuel.

You can't just use any type of uranium.

You need to use a specific type of uranium,

Uranium-235,

it makes up less than one percent

of all of the uranium

that you would find in nature.

They had to know how much of the Uranium 235 you needed to

make a bomb in the first place.

Then they had to separate out atom by atom,

physically ripping them apart,

the Uranium-235

from the predominant uranium that you find in the ground.

It was unknown how to even do that.

[narrator] One process they tried

was electromagnetic separation

with a device called a cyclotron.

It relies on gas containing uranium isotopes

235 and 238,

chemically indistinguishable,

but with a slight difference in atomic weight.

Electric current accelerates the particles of the gas

through a magnet.

[Dr. Koeth] You needed a large magnet

that was probably about 10 ft in diameter.

[broadcaster] The most powerful magnet in the world,

which will separate potent protons from the atom.

By the time they come out at the back end

of this magnet, they would have just

a few inches of separation

and you would collect them atom by atom.

The other methods included gaseous diffusion,

and that the lighter element, Uranium-235 would permeate

through, uh, a membrane easier than Uranium-238.

And, uh... But it's such a minuscule difference

that this would have to be done over, and over,

and over again through many thousands of stages.

[narrator] A third method use a massive centrifuge,

spinning uranium gas at extreme speed.

The U-235 and U-238 isotopes

collect at slightly different bands

alone the centrifuge wall.

For each method,

the equipment needed to be very large

to process as much material as possible,

even so generating only tiny amounts

of the prized U-235 each day.

There was another avenue

potentially for making this fuel,

which was to build nuclear reactors,

which had never been done before

and certainly not on an industrial scale.

And if you can get a nuclear reactor working,

then you can use it to generate

a man-made element, plutonium,

which you could also use in a bomb.

[broadcaster] The University of Chicago

in a secret laboratory, set up within the walls

of the stadium's squash courts,

a dangerous and partly unpredictable experiment

was undertaken.

In 1942, the physicist Enrico Fermi

and his team at the University of Chicago

created the world's first experimental nuclear reactor.

And this validated the idea

that you could build larger nuclear reactors

and use those to make a new element, plutonium,

which you could use as bomb fuel.

So, in the United States,

they decided they were gonna pursue

both enriched uranium and plutonium production,

even though they didn't know if either of them

could be feasible at an industrial scale.

They were betting on two horses.

[dramatic music playing]

[broadcaster] The entire USA program of uranium research

had been placed under the supervision of Dr. Vannevar Bush,

abled director of the Office of Scientific Research and Development.

The Office of Scientific Research and Development

was putting a lot of resources

into determining whether or not

they could build an atomic bomb.

Vannevar Bush, the head of the Office of Scientific Research and Development,

went to Roosevelt and said that if they brought in

the Army Corps of Engineers

who knew how to build large things,

that they could potentially have

an atomic bomb within two and half years.

And Roosevelt gave the go-ahead.

[whimsical music playing]

[car engine revving]

This work was assigned to the Manhattan Engineering District

located in New York City.

This would not just be a research enterprise.

This was going to be a project

to make actual atomic bombs

that could be used in war.

And to do this, they were going to construct

some of the largest factories on the entire planet

to strip uranium atoms from each other,

and to construct the first full industrial-sized

nuclear reactors ever created.

In order to do this,

you'd have to create an empire,

a new industry from scratch

that would span the entire country

and involved a labor of

hundreds of thousands of people.

And you need somebody who could command authority

over the military, over the government,

and over thousands of scientists

who are not accustomed to doing military research.

And the person they got for that

was Leslie Richard Groves.

Groves was an army engineer

who had graduated from West Point.

He knew how to build large things.

The most recent project he had worked on was the Pentagon.

And by his own admission,

he was the right man for this job.

[Gen. Groves] My natural characteristics,

what you can call dominant,

or brash or self-confidence,

or anything else you want,

but there were certain characteristics there,

that led to, uh, a very vigorous control.

For Groves, control and decisiveness were key.

[Gen. Groves] Make the decisions when they had to be made.

In other words, anything...

Any decision, a failure to make,

which would cause a delay

in the completion of the project,

uh, was made, uh, irrespective

of how much data was available.

[Dr. Wellerstein] And Groves, he immediately started scouting out

for sites to build these massive facilities.

He ended up selecting Oak Ridge in Tennessee

for uranium enrichment.

Um, Hanford in Washington State to build,

uh, industrial-sized nuclear reactors.

And finally, Los Alamos in Rural New Mexico

to have a secret laboratory for the scientists

working on the most sensitive design considerations

of the bomb itself.

[broadcaster] The war's most sensational secret.

It's a part of $2 billion spent

to beat our enemies to the punch

on the atomic bomb.

[Dr. Wellerstein] This whole operation, this whole new empire

was being called the Manhattan Project.

Groves is the type of person

who wanted to have the whole plan out

in front of him ideally.

He wanted to know exactly where he was trying to get to.

But when it came to this research,

he had to take a different approach.

[Gen. Groves] You know, it was different on the, uh,

our choice of, um, of three different approaches

to the separation of fissionable material.

The reason that was different

was that we had no idea as to, uh...

Whether we could do a particular one or not.

We had the feeling that, uh,

if we, uh, put everything on one plan,

that that thing might develop into a scientific roadblock

where you'd find that something is absolutely impossible.

[dramatic music playing]

At Oak Ridge, Tennessee, Groves created

an entirely new city from scratch.

The largest factories under one roof

in the entire world at the time

to separate out the uranium.

At Hanford, Washington, beside the Columbia River,

they built three industrial- sized nuclear reactors,

and all of the facilities necessary to convert

their output into plutonium.

Groves was in charge of recruiting

thousands of scientists and hundreds of thousands

of laborers from around the country to work on this,

all under a strict shroud of secrecy.

And yet, almost nobody working on it

knew what they were doing.

This was because Groves believed

that secrecy was paramount,

and the way he did this was through a policy

he called compartmentalization,

which was the need-to-know principle.

Everyone working on the project only knew

the bare minimum that they needed

to know to do their job.

But Groves knew what everybody was doing.

He was the one person who knew it all.

[dramatic music playing]

[narrator] What Groves, the US military,

and scientists didn't know

was how far the Japanese

and Nazi nuclear programs had advanced.

[broadcaster] The shadow of the conquering German armies

covered Western Europe.

The self-styled master race was riding high.

In the spring and early summer of 1940,

Germany appeared unstoppable.

One country after another fell to the German advance.

Major cities were invaded,

Rotterdam, Bordeaux, Paris fell.

The next in line would be London in Britain,

not through an invasion, but through an air war,

to be bombed into submission.

Now, Britain believes that the whole of Hitler's army

is turned towards their small island nation.

[Dr. Walker] The German Luftwaffe

was attacking British air bases,

military installations,

but then civilians were hit.

In response to British bombed German cities,

this enraged Hitler and he demanded retribution.

[speaking German]

[narrator] While the war was raging across Europe,

nuclear research in Germany continued.

Scientists from different universities in Germany

were summoned to Berlin for meetings

with army ordinance about the possible

military applications of nuclear fission.

An army physicist Kurt Diebner,

took over at the Kaiser Wilhelm Institute for Physics

as the army's personal representative

overseeing what came to be called the Uranium Club.

By late 1941,

it was clear to Diebner, Heisenberg,

and others that they had made great progress.

Experiments suggested that they could build

a large scale nuclear reactor.

They now understood that that would produce plutonium,

just like Uranium-235 a nuclear explosive.

In centrifuges appeared very promising

to produce that Uranium-235.

The theoretical physicist, Carl von Weizsacker,

in a patent application in 1941,

laid out how you could use

a nuclear reactor to produce plutonium,

which could be used in an atomic bomb.

This all begs the question,

why didn't Germany make atomic bombs?

The answer is,

as long as the blitzkrieg was going well,

Germany didn't need

what they called "Wonder Weapons."

That doesn't mean that they didn't support the work.

Albert Speer, the powerful Minister of Armaments,

over and over again personally intervened

to help the scientists working on uranium.

It's clear, even if he didn't count on nuclear weapons,

he had not given up hope for nuclear weapons.

[narrator] But the Nazi's success was about to change.

In June of 1941,

despite a non-aggression pact signed two years earlier,

German armies invaded the Soviet Union.

At first successful, the Nazi offensive

began to bog down in the harsh Russian winter.

[tense music playing]

[narrator] Russian troops had held the Nazis at bay,

but Hitler was determined.

In August of 1942,

he made a fateful decision.

[broadcaster] Despite the advice of his high command to the contrary,

the German leader ordered his sixth army

to open up the gateway to Asia

by taking the historic Russian city of Stalingrad.

Germany launched an offensive to capture

the City of Stalingrad,

to seize the oil fields there

and to protect the oil fields in Romania.

Hitler saw it as a prestige matter,

to capture the city named after Stalin.

[narrator] But the plan was ill-conceived.

At first, the Germans were very successful,

they occupied the city although at a great cost.

The Soviets encircled the Germans,

starved them out.

It's by far the biggest military

and propaganda failure of the Third Reich.

[dramatic music playing]

[plane engine revving]

[Dr. Walker] The German Home Front was becoming more and more desperate.

Widespread shortages were making life miserable.

Allied bombs were raining down on German cities.

It did not look good for Germany.

[plane engine whirring]

[dramatic music playing]

[narrator] In Japan, Nazi Helmuth Wohlthat

continued trade for Germany.

But he was feeling the pinch of the Allied blockade.

[Helmuth speaking]

[broadcaster] These pictures definitely show the end

of one of Adolf Hitler's cargos,

as a torpedo makes the final kill.

Britain controlled the seas.

Germany had to expect a blockade.

They had to expect that it would become

ever more difficult to get the materials

they needed to continue fighting the war.

Just like in World War I,

the Germans had one strategy

for breaking the British blockade.

Unrestricted submarine warfare,

that is attacks without warning

on shipping by the German U-boats.

[explosion]

[speaking in foreign language]

[narrator] In December 1941,

the attack on Pearl Harbor changed everything.

The US entered the war.

When the US entered the war, the blockade of German

and Japanese shipping increased.

Combine the British and the American Navies

and the British and the American Air Forces,

the result will be an immediate

and complete cleanup of the Atlantic.

He will then know...

[applause]

Hitler will then know what a blockade really means.

[applause]

Now, it's hunt and kill.

[dramatic music playing]

So by mid-1942, the Allies were convinced

they had a stranglehold on the Axis shipping.

[broadcaster] Official navy pictures of the smashing of a U-boat

surprised on the surface by carrier-based planes.

[explosion]

That's what we've always believed.

But it turns out the truth is a lot more complicated.

After the war, after the US captured

and interrogated Helmuth Wohlthat,

an important German economic advisor,

they discovered that this was wrong.

[dramatic music playing]

[Helmuth speaking]

What do you mean? What are you talking about?

[Helmuth speaking]

[dramatic music playing]

What is so surprising, if not shocking,

is that so much got through.

Wohlthat could send so much to Germany

without the Allies having any idea.

[narrator] Wohlthat's records change

our entire understanding of the Allied blockade

against German and Japanese trade.

Was Nazi uranium part of his cargo?

December 1942 back in Europe,

the Nazi's were losing ground.

[Dr. Walker] By late 1942 the German advance had stopped.

It was clear that the war had turned against Germany.

It's pretty simple, it's the same thing

Napoleon found out, you know,

fighting in Russia is great

until you hit November.

The Allied attack on German cities

had become so fierce.

[narrator] The Nazis needed a wonder weapon.

But their nuclear scientists

were facing huge obstacles

and constant fear.

[Dr. Walker] Factories that were making the centrifuges

were bombed flat.

The metal uranium for the nuclear reactors

could not be cast.

And the scientists themselves

were in perpetual fear

that they would be called up

to fight on the front as common soldiers.

[narrator] Relentless air attack made their labs unsafe.

The German scientists were repeatedly forced to move

to more obscure locations.

The uranium project scientists

found it increasingly difficult

to do experiments, to get materials.

[narrator] And experiments often failed.

No one had ever harnessed nuclear energy,

much less made a bomb.

Heisenberg and Dopel the German nuclear scientists

were working on a version of reactor

called the L-IV and it was in Leipzig.

It was starting to show positive results.

They were starting to see neutron multiplication.

But the L-IV reactor was a spherical configuration

where uranium powder was being poured

into the metal sphere.

Uranium metal when it's a fine enough dust,

just when it comes into contact with water

or even moisture and air will catch on fire.

Uranium caught fire,

jettisoned hot gasses right out the fill tube

and the uranium burned for days.

They were unable to put it out

because it was such a hot, intense fire.

The Germans had also experimented

with the early versions of centrifuges

and of course that failed catastrophically

when the high speed caused the material

to just break under the extreme forces

and disassemble itself.

[machine whirring]

But again and again,

just when it appeared that

the research would grind to a complete halt,

Armaments Minister Albert Speer intervened.

He gave them the highest priority

for their experiments,

for acquiring materials,

for getting the labor they needed to continue.

It's clear that he was infatuated

with the prospects of nuclear weapons.

[explosion]

[narrator] By 1943, Japan's nuclear effort

was also struggling with limited resources

and scientists, and Allied bombing raids.

In America, despite safer conditions,

scientists had no idea yet how to make a bomb.

[Dr. Wellerstein] In the United States, the biggest hurdle

was still to make enough fuel for the bomb.

General Leslie Richard Groves

constructed massive facilities

for the enrichment of uranium

and for the production of plutonium.

[narrator] After millions of dollars

and thousands of man hours,

they were still only able to produce

tiny amounts of bomb fuel.

Here it is General Groves, plutonium.

Well, that's, uh, the first time I've seen it.

But if you don't mind, I wish you'd hold that under

because after all, there's over $50 million

in that tube.

But it still wasn't clear

whether any of these methods were going to work.

[broadcaster] After six weeks of heavy combat,

men of the US First Army

broke out at a place called Saint-Lo

and began pursuing the fleeing Nazis across France.

[Dr. Wellerstein] So the Allies were making significant gains

against Germany.

They were pushing through France,

they were liberating Paris.

[crowd cheering]

But the Japanese war was still going on.

[narrator] In 1942

before the tide of war changed in Europe,

battles raged across the Pacific theater.

The Battle of Midway in 1942

was devastating for the Japanese Navy

and really called into question

the Japanese strategy.

[broadcaster] American carrier-based aircraft assisted

by land-based planes turned the tide of war

in the Pacific off the island of Midway.

[bomber plane whirring]

[narrator] The Japanese were losing the war.

[plane explodes]

[narrator] But they were not going to give up.

[Dr. Grunden] The Japanese Army ordered Nishina Yoshio,

their premier physicist of Japan, to build a bomb.

Nishina of course knew that massive amounts of U-235

were going to be needed to reach a critical mass.

But just how much uranium they would need,

no one was certain.

In Japan, the storage of uranium were very limited,

but they scrounged around to find

what they could just to begin experimentation.

The army dispatched investigation units

far and wide.

They went to Mongolia, they went to Burma,

they went all over Southeast Asia

looking for possible stores of uranium.

Japan faced the same problem as Germany,

how were they going to enrich

enough Uranium-235 to build a bomb?

With its limited natural resources,

its limited industrial capacity,

it didn't have a lot of options

to pursue for enrichment.

The Navy tried to construct a centrifuge,

but they didn't get very far

because they lacked the important necessary materials.

Nishina thought perhaps

the best route would be the cyclotron.

They were working on the large 60-inch cyclotron.

But it did not have the electrical capacity

to produce the enriched uranium

that they would need.

One scientist calculated with what they had on hand,

it would take at least 15 years

for Japan to develop enough enriched uranium

to make a bomb.

After months of research and months of trying,

all they'd come up with is a small crystal

of a kind of enriched material

that's only about the size of a grain of rice.

They're under enormous pressure to produce,

especially for the Army.

Nishina realizes he doesn't have enough uranium

to make any sort of reactor.

He gives up on the reactor idea altogether.

They're really just thinking towards a bomb.

But if they're going to build a bomb,

how are they going to get there?

What is the process?

What is the means they're going to use

to enrich enough uranium?

They don't have enough uranium ore.

This is the problem that keeps plaguing

the Japanese project

from the start to the finish.

This is why they need Germany's help.

But they were both suspicious of each other.

[dramatic music playing]

[radio static]

[narrator] Winning World War II

would hinge on who built the bomb first.

Intercepted communications hinted

that both Germany and Japan knew this.

Their nuclear research

depended on the supply of uranium.

[Dr. Wellerstein] Japan asked Germany to send them uranium,

specifically uranium oxide and pitchblende

which is a uranium-bearing ore.

September 1st, Berlin agreed to acquire

the pitchblende for Japan,

but they wanted to know what it was gonna be used for.

[suspense music playing]

[Dr. Wellerstein] And Japan responded that it was gonna be used

as a catalyst for fuel production,

probably a lie.

On November 2nd, 1943,

the Nazis informed Tokyo

that while they couldn't send pitchblende,

they could supply one ton of uranium oxide.

[narrator] Uranium oxide is a processed form of uranium

that could be safely transported.

[Dr. Wellerstein] But as far as we know, nothing happened,

not until the two allies agreed

to a technical exchange agreement

in March of 1944 did the Nazis begin

sending their latest technology, weapons,

and technical expertise to Japan.

[narrator] Did this include nuclear materials?

In the United States,

nobody had any hard information

about whether or not

the Germans were getting close to an atomic bomb.

And there was a growing fear, maybe even a panic

that they were getting very close to a weapon.

And if Hitler had a nuclear weapon

and the United States had no means

to threaten them back or even retaliate,

there was a fear that that could be the end of the war

despite so many allied advances against the Germans.

But the Manhattan Project scientists

almost unable to focus

because they were so worried about the Germans.

General Groves brought in 2nd Lieutenant Robert Furman.

[Gen. Groves] I went into the Manhattan District,

very quiet, very secretive.

General Groves brought me in

to try to calm down the scientists

who he had working on this project to develop the bomb.

The scientist wouldn't concentrate on their work.

They were scared that

the Germans were years ahead of us

and would bomb us almost immediately.

My job was to work with them

and try to calm them down

and get them back at their...

In their laboratories and at their desks.

Groves put together a secret mission

to go into Europe

and discover what the Germans

were actually doing,

how far along they actually were.

And they called this Alsos which is Greek for Groves.

Now a major, Robert Furman

assists Groves in managing Alsos.

[Gen. Groves] The scientific mission built on fear.

Fear that the enemy had the bomb

or would have it before we could develop it.

And this they knew to be the case,

the scientists did, because they were refugees from Germany,

a large number of them, and they had studied

under the German before the war broke out.

I knew of 48 different German scientists

that could be involved in a project

that could develop a bomb.

[suspense music playing]

[Dr. Wellerstein] In December of 1943, the first Alsos Mission

was arriving in Italy

and interrogating Italian scientists

to learn about German work.

Back in the United States, the Manhattan Project

was struggling to put together the systems

that would generate enough fuel to make a bomb,

both the enriched uranium and the plutonium.

There were many, many trials, many pilot plants,

and they were failing repeatedly.

Things that had seemed like pretty sure bets

were proving to be extraordinarily difficult.

In May of 1994, Joseph Slepian,

headed Westinghouse's Research Division,

feverishly building a massive ionic centrifuge

to separate Uranium-235.

Slepian wrote to J.B. Conant

of the Office of Scientific Research and Development,

"Tests with the smaller model centrifuge"

is showing enhancement of uranium by one percent.

Construction of the larger unit

"is a bit behind the expected schedule."

Over a month later on July 5th,

Slepian reports on trials

with the finally completed ionic centrifuge.

All three runs failed completely.

[broadcaster] With this potent machine

and others that will be even more powerful,

US atomic scientists are determined

to maintain their nation's lead

in their struggle to unlock

the innermost secrets of the universe.

[Dr. Wellerstein] And at Oak Ridge, Tennessee,

the world's largest electromagnetic separators

were still struggling.

Ernest Lawrence wrote to Groves

that the electromagnetic process

was in a fluid state of development.

They were beginning to produce Uranium-235

but not in the process and quantity

that they would need to get a bomb.

And at Hanford, Washington, the production of plutonium

was also going slowly.

Lawrence even suggested that efforts should be made

to develop brand new equipment

for the enrichment of Uranium.

And Groves was desperate enough to do it.

[ominous music playing]

[Dr. Wellerstein] So in Germany,

the Alsos Mission was immensely successful.

They were following directly behind American advances,

sometimes even a little ahead of them,

in order to capture German scientists,

documents and laboratories.

They were beginning to piece together bit

by bit exactly what the Germans

had been working on.

[narrator] Alsos found that the German atomic bomb

program was further behind than the US thought.

[Dr. Wellerstein] America had felt that it was

in a race with Germany.

But in reality, it was racing against itself.

Interestingly, the pace and direction

of the American program really didn't change

at that point.

Even when they found that the Germans

were no longer a threat.

Instead, it became a race against time

to make all of this effort worthwhile.

And in this case, that meant to make a bomb.

[reporter] Scientists of many nations working

feverishly to harness cosmic power for a war and peace,

working on the atomic bomb, most astounding news

of this century.

[Dr. Wellerstein] By late December 1944,

many of the problems of producing Uranium-235

were starting to be solved.

But they're gonna need to increase their output

quite a lot if you're going to be able

to make enough nuclear material to use in a bomb.

A now declassified communique showed

that the production of T, uranium-235 would still have

to increase by a factor of nearly two

and a half times.

And in late February 1945, Slepian at Westinghouse

finally admitted to Conant that their approach

was not going to work.

We are finally driven to the conclusion

that we were not able to predict the motion

of the ions as well as we had thought.

I am much less certain of my ability to pre-design

a practical apparatus.

[narrator] Problems played every aspect

of the Manhattan Project.

But there was a glimmer of hope.

[Dr. Wellerstein] Some of their methods were showing some promise.

The electromagnetic method, gaseous diffusion,

and even thermal diffusion were showing some promise.

But no one of them seem like they were gonna work.

And this is around when they had the idea

to chain them together.

With promising methods on the horizon but the end

not yet fully in sight, Groves really felt

that he needed everybody focused on the task at hand.

At this point, Groves overrode attempts

to introduce new equipment and change methods,

understanding that the costs and time

on the project would be too high.

Groves believed that at this point,

they were committed to the ones that seemed

the most promising.

[dramatic music playing]

[narrator] In Germany, the scientists knew

the war was coming to an end.

But fighting in the Pacific had intensified.

Pressure mounted on Japanese scientists

to create a wonder weapon.

Would Germany help?

[crowd cheering]

[narrator] Victory in Europe, V-E Day,

all Nazi military operations were to cease.

In the middle of the Atlantic,

a German submarine, the U-234 received the message.

It was on its way to Japan with special cargo.

This was the Nazis last-ditch attempt

to get high technology to their allies in Japan.

And on board, the submarine U-234,

were two Japanese officers, a German general,

engineers, and scientists.

And in her hold, the submarine carried

the latest German weapon technology,

including a crated Messerschmitt

Me 262 jet fighter

and the newest electric torpedoes.

[suspense music playing]

[Dr. Walker] The German submarine surfaces

is taken by American forces and brought

into Portsmouth Harbor.

[narrator] As it's unloaded, the US is surprised to find

nearly a ton of uranium oxide.

The Japanese Ambassador Oshima had requested

tons of pitchblende and, uh, uranium-bearing ores

from Germany.

Two U-boats were dispatched to Japan

that were carrying these uranium compounds.

[machine gun firing]

One of those U-boats was sunk en route

probably somewhere around Singapore.

But the other one was U-234.

Some ten gold lined cylinders of uranium ore

were discovered on board.

And these went off to Indian Head, Maryland.

But there, the trail goes cold,

we don't know what happened to that uranium thereafter.

These are the only two shipments

that had been recorded that historians

even know about.

[narrator] But newly discovered documents reveal

that the Nazis attempted other shipments of uranium.

We found these records in your office.

This is your inventory.

[man speaks]

They cover a period from the 15th of December 1944

to the 30th of April '45, is that right?

[man speaking]

I see.

Tin, palm oil, rubber?

[man speaking]

Wolframerz or tungsten ore,

opiumn, jod, and iodine.

And on page one, the fifth item.

[man speaking]

2.2 tn in December and 3.2 tn

by the end of April.

So here is the Nazi uranium in a warehouse in Kobe.

So this is new information.

This changes our understanding of the story.

Wohlthat's records record show us that the Germans

got uranium to Japan and they did it

by ship despite the blockade.

The discovery of so much uranium in Kobe

is a big surprise because the United States

had sent scientific intelligence investigation

teams all throughout Japan after the war.

And they accounted for all the uranium-bearing ores

that were there or so they thought.

How did it get there?

What was the chain of custody?

These are all things that we need to know.

So it opens up a new chapter in history.

[suspense music playing]

[narrator] In early 1945 in Germany,

the Nazi nuclear program was struggling

under the weight of allied bombing.

[Dr. Walker] Heisenberg's last experiment

had been moved Berlin to the sleepy little village

of Haigerloch.

They're in a rock cellar.

They set up the last B8 experiment.

Uranium cubes immersed in heavy water.

Six hundred and sixty-four Uranium cubes

roughly two in on a side, weighing about five lb.

In strings of either eight or nine cubes per strand.

The whole sample would be lowered

into a pool of heavy water.

[narrator] Heavy water contains deuterium

which increases the chance of a nuclear chain reaction.

[Dr. Koeth] And this is where the Germans had their

last-ditch effort to make a working nuclear reactor.

How close did they actually get?

The Alsos Mission discovered

the remains of the B8 reactor that have been

scattered around Haigerloch.

They dug up 659 of the 664 cubes

that had been part of the reactor.

They also discovered the heavy water,

which have been stored in jugs in a nearby mill.

And all of the pertinent documentation

had been dropped down a latrine.

They shipped it back to the United States.

The last mention we have of this

is from General Groves where he says it was shipped

in the United States under the purview

of the Combined Development Trust.

An agreement between the United States

and the United Kingdom to try and corner the market

on uranium globally.

What if Germany had gotten to the atomic bomb

before the United States did?

[suspenseful music playing]

[narrator] Tim Koeth is a physicist fascinated

with nuclear history.

What the Alsos Mission showed is that

they were far away from an atomic bomb.

And they were not so far away from making

a working nuclear reactor.

[narrator] But Tim never expected to have

a direct connection to the Nazi reactor

in Haigerloch.

I was out for a jog on August afternoon

and I got a phone call from a friend who said,

"I think I have something you would really like to see.

Meet me in this parking lot."

Fifteen minutes later, I come running out

of the woods, popped open the trunk,

and we looked in, there's a little brown bag.

I could just see a corner of this cube

with a telltale notch peeking out,

and I immediately knew what it was.

The cube of Uranium from Haigerloch.

With my curiosity piqued, I started investigating.

But then I came across a link to the National Archives

and one of their finding aids referred to a box

that was labeled German Uranium cubes.

And I thought that had to have been

the answer to my question, what happened

to the 664 cubes?

But, no, that was not what I found.

First, I was initially disappointed

and about 15 seconds later, I was, uh,

just dumbfounded by what I had discovered.

And that there was another 400 cubes

they were referring to.

So this was first definitive proof

that there was an addition to the 664 cubes,

another 400 cubes.

This should have been enough for Germany to have built

a working nuclear reactor.

This is history-changing.

So this is the cube from Ninninger.

It was wrapped with a note that reads,

"Taken from Germany from nuclear reactor

Hitler tried to build.

Gift of Ninninger."

So who exactly was Ninninger?

So we look at the org chart for the Murray Hill area

of the Manhattan Engineer District,

we can see Ninninger's name listed here

under the executive branch.

So he was a member of this group of people

to whom we think the 659 cubes

that were discovered at Haigerloch

were shipped, too.

So the other 400 cubes are described

in another set of documents at the National Archives

and this is the first document in that series

that describes the black market

that formed in Europe paddling these cubes around.

This is pretty funny.

It reads, "It appears that the members

of a ghostly gang are gradually taking shape."

Who writes... communiques like that today.

So the last document in this series talks about

what they think happened.

Um, so it notes that every time the cubes

came up for sale, they would, um,

be accompanied by a threat that if the US

didn't purchase them, they would be shipped

to the USSR.

Um, so the last line here says, it seems that at last

that this threat has materialized.

So it looks like that's what happened to the cubes.

The final disposition of the 400 is the USSR?

Looks like it.

There... There was a few cubes that exist in the world.

And a few of them have been examined

in a number different ways.

Gamma-ray spectroscopy tells us

that there's absolutely no way that the B8 reactor

ever went critical.

It was acknowledged by Heisenberg and the other

scientists at the Haigerloch site that approximately 50%

more cubes were necessary and equivalent

amount of heavy water.

And they thought that at that point

they would have a self-sustaining

chain reaction.

[narrator] Tim and researcher Patrick Park

are using a computer model to find out

what would have made the Haigerloch reactor work.

So you can see my recreation on your screen now.

Patrick, your model of the B8 reactor

is quite exquisite.

I'm curious what the new program,

uh, results are.

[narrator] Analyzing key variables,

the program predicts if the reactor would go critical,

a self-sustaining reaction

with a K-effective value of one.

Uh, we're gonna ask it to compute

the K-effective, 0.934.

So that's almost critical.

[narrator] Heisenberg's Haigerloch

reactor was close to success.

To find out what would have made it go critical,

the first change is to increase

the number of cubes.

So we'll be putting in a total of 897 cubes.

[narrator] Two hundred and thirty-three more

than the original Haigerloch core in Germany.

The computer recalculates the model.

0.95, we're approaching criticality.

- Uh, we're not there yet. - [Patrick] All right.

Uh, but we're definitely going in the right direction.

[narrator] They tried increasing the space

between the cubes.

[Patrick] 12.5 cm.

[Tim] Oh, the K-effective comes back at 0.924.

[narrator] And the diameter of the core.

Nothing works.

They have one final variable to try,

the purity of the heavy water,

the moderator that slows neutrons down

and increases the chance of fission.

Patrick estimates a purity of 98.3%.

The model confirms your calculation.

Uh, K-effective is exactly 1.000.

So had there have been a sufficiently

high purity plus the full inventory

that was available to the German scientists,

they could have made a working nuclear reactor.

[Patrick] Fantastic.

Excellent.

[narrator] If Heisenberg's reactor experiment

at Haigerloch succeeded, would it have put

the Nazis closer to a bomb?

[dramatic music playing]

[reporter] The Nazi Swastika is blotted out

by the Stars and Stripes.

[Dr. Grunden] Germany surrenders in May of 1945.

The war in the Pacific becomes

exceedingly desperate for the Japanese.

[canon firing]

The Japanese have to realize it's over.

They're the only Axis power remaining to fight The Allies.

The Allies had taken a two-pronged approach.

General McArthur leading the army

and the marines toward the Philippines

and Admiral Nimitz for the navy driving

toward the heartland of Japan.

So they were taking islands across the Pacific,

getting closer and closer.

So the writing is really on the wall

for the Japanese at this point.

They turned to suicide tactics,

Banzai charges, Kamikaze planes.

The United States also realizes

that the war is coming to a conclusion.

But there is another problem,

the Soviet Union.

[explosions]

[narrator] The Soviets had defeated

the German offensive and anticipated

that Japan would fall.

They were aggressively expanding their territory.

[Dr. Walter] If the Soviets get a foothold in Japan,

Japan will be divided like Germany.

And the United States does not wanna see

a divided Japan.

In fact, it wants to keep the Soviet Union out

of East Asia as much as possible.

In the United States, there was tremendous pressure

from the people at the top

of the Manhattan Project, to get these bombs built

and have them used.

[narrator] The war in the Pacific

was continuing to have a high cost in human lives.

[Dr. Wellerstein] Groves believed the bomb

might help end the war.

He felt that it would help against the Soviet Union

in the post-war.

But they still didn't quite have enough fuel

and they weren't still sure of the bombs would work.

On July 16th, 1945, the United States

tested the world's first atomic bomb in the deserts

of New Mexico.

And they called it Trinity.

[suspense music playing]

[explosion]

[reporter] Army cameras six miles away...

[Dr. Wellerstein] And it exploded with a violence

of over 20,000 tn of TNT that could be seen

for 80 mi and heard for 50 mi.

It turned that desert sand

into a green radioactive glass

and made a column of smoke that went up

over 30,000 ft in the air.

Everyone who saw the test was awestruck by it.

We tend to think of the Manhattan Project

as a project to just build an atomic bomb

or the atomic bomb, but it's really building

a system for building lots of atomic bombs.

But at this point, they were just trying to get

the minimum amount of material you needed

to build the very first bombs to use in the war.

And they still had to not only make that material

and make it into the right shapes to be used

in the bombs, but to also ship it out

to the front and then assemble it into weapons

that could be dropped out of airplanes

over a Japanese city.

So there was still a mad push after Trinity

to get the bombs used in combat.

[narrator] J. Robert Oppenheimer

was the head of the Los Alamos project.

Orchestrating all of the facilities

and people needed to build a weapon.

[Gen. Groves] In other words,

everything was scheduled on the basis

Oppenheimer's whole time schedule,

you must be ready to ship the bomb to have

all the thing connected with the gun-type bomb

as soon as you get the material from Oak Ridge.

At long last,

their facilities were actually producing

the uranium and the plutonium they needed for these weapons.

They were actually getting to the point now right

at the finish line that they could start

using them.

On July 30, as Groves wrote to General Marshall

with the news that the production

of bombs was increasing, they were gonna have

three nuclear bombs ready in August,

maybe four in September, and again in October.

But there were still uncertainties

and they weren't completely sure

that they would actually work as intended

over real world targets.

[reporter] A feverish scientific labors to harness

atomic power ahead of the enemy.

[narrator] General Groves sends his assistant,

Robert Furman, to Los Alamos to take the bomb

to the Pacific theater.

[Robert] General Groves sent me out to pick it up.

And I remember that the authorities at Los Alamos

wanted a receipt that I had received it.

So I signed a receipt for an atomic bomb

and I traveled with the bomb first by air to California,

and then the cruiser Indianapolis to Tinian.

And Tinian s the island

from which the Enola Gay the B-29 that flew

the atomic bomb to Hiroshima was launched.

Dropping the bomb was a massive gamble.

[Gen. Groves] We didn't know

whether that thing would go off or not.

[suspenseful music playing]

[narrator] At 8:15 AM on August 6th, 1945,

the devastating power of an atomic bomb

was dropped on the Japanese city of Hiroshima.

[explosion]

[Dr. Wellerstein] Days later, Al Zelver,

a Japanese language translator flew directly

over the ruin city.

[Al] The pilot flew very low

and he circled in both directions,

and he tipped wings so each of us get a good

look on both sides of the plane.

And I thought, well, if you've seen

one bombed out city, you've seen them all.

But that's not true.

The Blitz in London, it took about six months

with hundreds of raids and 40,000 people

were killed.

But not a lot of London was destroyed.

Forty thousand people is a lot of people

but it's only half a percent of the population

of eight million.

In Hiroshima, it's a second,

with one bomb and one plane,

it obliterated two thirds of the buildings

and it killed a third of the population.

So that's a very different order.

[Dr. Wellerstein] So Hiroshima was terrible,

but would it actually end the war?

Would it cause the Japanese High Command

to surrender?

And the Japanese High Command learned that Hiroshima

had been bombed shortly after it had been attacked,

but they didn't know it was an atomic bomb.

[Dr. Grunden] The devastation was so great.

No one is really certain what happened.

So, Nishina Yoshio, their premier physicist

of Japan was dispatched to Hiroshima.

On the evening of August 8th 1945,

Nishina cabled back

that it was an atomic bomb and that Hiroshima

had been totally destroyed.

And it was... It was shocking

because no one thought that a bomb

was going to be ready for this war.

[suspenseful music playing]

The Japanese High Command

agreed to meet the next day to discuss this,

but over that same night, the Soviet Union

renounced its neutrality, declared war on Japan

and invaded Manchuria.

Both of these events

had a strong impact on the Japanese High Command

and seemed to dash any hopes that there could be

a diplomatic or military resolution to the war

that would be in Japan's favor.

And while they were at this meeting,

they got news of the Nagasaki attack.

[explosion]

On August 10th 1945,

General Groves wrote to General Marshall

that a third atomic bomb would be ready to use

on Japan in about a week.

And Marshall conveyed this information to Truman,

who personally rejected this.

Marshall conveyed this back to Groves immediately

that it is not to be released over Japan

without express authority from the president.

The world had witnessed the devastating power

of the atomic bomb twice.

[reporter] The Battleship Missouri

anchored in Tokyo Bay, the historic moment

that the world had anxiously awaited

for almost four bloodstained years

was about to take place.

[people chattering]

Finally, on August 151945, the United States accepted

Japan's unconditional surrender.

[reporter] Mamoru Shigemitsu, the foreign minister

of the Japanese Surrender Government

removed his white gloves for the historic signing.

[dramatic music playing]

[narrator] The bomb ended the war.

But Japan's nuclear ambitions had collapsed months earlier.

[Dr. Grunden] An American B-29 bombing

raid leveled Tokyo.

Building 49 of the Riken was severely damaged.

The two cyclotrons remained intact,

but the rest of the building collapsed,

taking with it the rest of Japan's nuclear project.

[ominous music playing]

The Germans could not have made

an atomic bomb during World War II.

Could they have built an operating nuclear reactor?

The answer is certainly, yes.

[Dr. Koeth] If the Germans did have

sufficient heavy water, having this additional

400 cubes in their inventory,

had they been at the same location at the same time,

this could have enabled them to have built a working

nuclear reactor bringing their program further along

than they're given acknowledgement for.

At most, the Japanese

had a few hundred people on their atomic bomb project

and the Germans might have had a bit more than that,

maybe a thousand or more.

The United States employed 500,000 people over the course

of World War II to build its atomic bombs.

And that's why the Manhattan Project

was the only atomic program of World War II

to truly succeed.

[dramatic music playing]

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