Original subtitles

Man has long applied the latest science

to the creation of weapons,

but the industrial age has seen unprecedented leaps

in man's capacity to manufacture

ever more powerful machines,

machines capable of inflicting death and destruction

on a massive scale.

From hand grenades to howitzers,

flame throwers to high explosives,

and of course the ultimate in devastation,

the atom bomb.

This is the story of modern man's insatiable desire

to land the killer blow

on the pathway toward mass destruction.

(dramatic music)

Canon's first appeared on battlefields

in the late 1300s.

And during the Middle Ages,

they became standardized, more common and more effective,

both in siege roles and against infantry,

effectiveness that led Shakespeare

and his playing Henry the IV to have the character Falstaff

describe his man before battle as food for powder.

Cannon fodder was to become the popular term,

but not even Shakespeare could have imagined

the power of the artillery designs of the 20th century.

Technology that would create food for powder,

the like of which had never been seen before.

The French 75,

(gun firing)

the gun from which all modern field artillery is descended.

The Canon de Soixante-Quinze modèle 1887

was the world's first truly modern artillery piece,

and instantly made every other field gun

in the world obsolete.

Every major offensive that the French army took part in,

in France on the Western front during the First World War,

the French 75 would be the key part

in the preliminary artillery bombardment.

Weighing only 1500 kilograms in action,

it fired a 75 millimeter shrapnel round

weighing seven kilograms out to a range of 6,850 meters.

But what was revolutionary about the French 75

was that its seven man crew

could maintain a steady firing rate

of up to 15 rounds per minute.

This unprecedented ability to provide rapid accurate fire

was achieved by using a new and ingenious

hydro-pneumatic recoil system.

The recoil mechanism in this French 75

meant that it can come automatically back

to its original fire position

and did not have to be re-aimed before it was fired again.

The entire cycle,

including the return took just two seconds.

The gun also featured an all new rapid-acting

screw-type breach mechanism

into which was loaded an innovative fixed round

with the time-fused shrapnel filled

projectile and propelling charge

pre-packaged in a brass case,

which could be loaded in a single action.

(explosion booming)

A combination of innovations in a single weapon

that led to destruction on a scale

that had never been seen before.

It is estimated that the allies alone

fired over 5 million tons of shells during the Great War

and the Germans, perhaps as much again.

In all, over a billion projectiles plunged through the air

in just four years.

And when it wasn't raining lead,

a deadly fog would drift in.

On the evening of April 22nd, 1915,

allied troops looking across no man's land

in Southern Belgium saw a strange greenish-yellow cloud

drifting toward them.

The Germans had released 170 metric tons of chlorine gas

along a six kilometer stretch of the front.

More than 1100 troops would be killed

and 7,000 injured in what was the world's

first large-scale use of chemical weapons.

The confined trench systems of World War I

were ideal for achieving effective concentrations of gas.

However, when it was released from cylinders

on the prevailing wind as it was that day,

it was impossible to control.

Firing gas at the enemy using artillery was the solution.

Chemical shells were first introduced by the Germans in 1916

using 150 millimeter artillery.

Independent of the wind,

delivery of chemicals became a much more accurate affair.

But gas, like any weapon evolves

as a result of battlefield experiences.

The main flaw associated with delivering gas via artillery

was the difficulty of achieving a killing concentration.

Each shell carried only a small payload

and an area needed to be saturated

to produce a cloud to be deadly.

And both sides develop countermeasures,

some primitive, others like gas masks

becoming increasingly sophisticated.

To nullify this in 1917, the Germans introduced a chemical

which did not need to form a concentrated cloud

to be effective.

Mustard gas.

A volatile, oily liquid that was heavier than air.

Having settled on the ground and in the soil,

mustard gas remained active for weeks,

even months, depending on the weather conditions.

Poisoning was by contact.

Troops would march through contaminated areas

unaware that they were being exposed.

After returning to their trenches or barracks,

they would then contaminate other soldiers.

After contact, the skin of victims would blister.

Troops would begin to vomit,

suffer internal bleeding and eventually blindness.

Between 35 million and 66 million shells

filled with chemicals were fired during World War I.

Although the strategic power of gas

was not in the number of soldiers it killed,

less than 1% of fatalities and only 7% of casualties

were attributed to chemicals.

It was in the psychological terror they caused,

fear that in World War II would be delivered by size

and on land, the largest allied weapon

of the Second World War was the American M1.

Introduced in 1943, the Black Dragon as it was called,

was designed to penetrate thick concrete fortifications

like those the allies expected to encounter

along the German's Siegfried Line.

The key to its destructive power was its caliber.

The larger the caliber, the faster the projectile,

the higher the payload you can accelerate.

You deliver a much more intense,

a much more dangerous explosive payload to the target.

In the case of the Black Dragon,

that amounted to a huge 240 millimeter explosive projectile

that weighed 160 kilograms

fired out of an 11 meter long barrel

to a distance of 23 kilometers with pinpoint accuracy.

(M1 firing)

(explosion booming)

Each shell impact from the M1 left a crater

more than two meters deep and eight meters wide.

And the radius in which a soldier

could be rendered a casualty was unprecedented.

For an un-entrench prone man

up to 40 meters from detonation,

death was almost certain.

At a hundred meters from the blast,

that same man would have a 50% chance

of becoming a casualty.

And potentially deadly shrapnel fragments

could be thrown as far as one kilometer away

from the point of impact.

But the Black Dragon was a towed artillery piece.

Before it could be fired,

it had to stop, uncouple,

set up and dig in.

To fully exploit a tactical advantage

on an increasingly mobile battlefield,

it soon became clear that the artillery

most capable of capitalizing on that advantage

should also be mobile.

All arms battle is dependent on uniform speed of action,

tanks, infantry and artillery all working together.

And as the Cold War got chilly,

the Americans introduced a mobile weapon

of extraordinary destructiveness,

the M109. (M109 firing)

The original M109 was introduced in 1962.

And with its seventh update, the Paladin,

every aspect of its destructive capability

has been enhanced.

The M109 Paladin is a self-propelled howitzer.

And so what that means

is that you have a 155 millimeter gun fitted

to a vehicle chassis.

The addition of gun stabilization systems,

automated gun laying and loading systems,

to the 1960s chassis makes the Paladin

capable of sustaining four rounds per minute,

for four minutes without fully in placing.

Together, a battery of six Paladins

can deliver over a ton of ordinance permitted

for each of those four minutes,

an immense weight of destructive power

delivered to a target.

And the firing range of the Paladin

has been extended from 24 to 30 kilometers

with conventional shelves

by fitting of a longer, lighter six meter barrel,

range that extends to 40 kilometers

with the use of rocket-assisted guided projectiles.

Pull!

(M109 firing)

And it is those shells that do the damage.

Improvements in high tensile steel

has led to a reduction in the thickness of shell walls

without loss of structural integrity,

which has in turn allowed shells to carry more explosives.

This combined with improved explosive compounds,

give the M109 Paladin a casualty effect 400% greater

than a similar weapon from World War II.

Less steel, more destructive power,

more accurately delivered.

The M109 is currently undergoing a further update

that will no doubt increase its ability

to deliver heavy blows from well behind the front lines.

(M109 firing)

(explosion booming)

But for an infantry man in the heat of battle,

destruction is up-close and much more personal.

Small bombs have been used in warfare since ancient times.

The Greeks deployed fire bombs in antiquity,

and since the invention of gunpowder,

early versions of hand grenades

with dangerously unpredictable smoldering fuses

had been cautiously deployed mainly in siege situations.

Considered obsolete at the outset of World War I,

the demands of trench warfare saw the idea

of hand grenades resurrected,

redesigned and emerge as an indispensable item

in the foot soldiers arsenal.

Grenades put the destructive power

of an artillery strike in an infantry man's pocket.

And while initially they were thrown,

the desire to project them farther

led to developments that allowed the infantry man

to expand his destructive reach beyond arm's length.

In the latter stages of World War I,

riflemen Lewis gunners and grenadiers

were joined by the rifle grenadier.

Rifle grenadiers fired a standard grenade

fitted to a steel rod launched from an infantry rifle

using a blank charge out to a range of up to 150 meters.

A cup-type launcher was introduced later in World War I,

a system that persisted through World War II,

but using a propellant to kick the projectile

out of a barrel creates recoil,

and it is recoil that limits both the range

and the size of the projectile that can be fired.

It was the adoption of the high-low

pressure ballistic principle

that revolutionized grenade launches

and led to weapons like the M203.

The projectile in the M203

is sent in a bi-chambered cartridge case

with propelling cup fitted into the base.

The cup contains the propelling charge

and acts as the high pressure chamber,

and the hollow cavity of the case,

which surrounds the cup acts as the low pressure chamber.

When fired, the high pressure

does not directly act on the projectile

as it would in a standard gun.

But instead that pressure is allowed to bleed gradually

into the hollow outer cavity at a controlled rate.

This lower pressure then shoves

rather than kicks the projectile out of the barrel

at a constantly increasing muzzle velocity

dramatically reducing recoil.

As a result,

the M203 which weighs just one and a half kilograms

and attaches under the barrel of an infantry rifle

fires a relatively large 40 millimeter shell

weighing a quarter of a kilogram

out to a range of 400 meters from a standing position.

Weight and range that with a standard firing system

would produce recall beyond human capabilities.

And each high explosive grenade carries 32 grams

of modern composition B explosive.

And once you detonate the explosive,

that sets up a chemically supported shockwave

within the explosive material.

That shockwave would move between five

and eight kilometers per second.

And it's the shockwave that does the damage to vehicles,

it kills people and it destroys structures.

While they don't release shrapnel

in the quantities of the French 75,

M203 shells have a similar casualty radius.

And the arsenal includes rounds

that can breach 75 millimeters of steel

and a range of incendiary grenades.

But incendiary weapons,

like so much of the machinery of war

have a history all of their own.

In August, 1942,

when the US Marines began the offensive

on the Solomon's Island of Guadalcanal,

they encountered numerous underground fortifications

built by the Japanese.

Direct assaults on those interconnected tunnels

proved extremely costly.

And to clear them,

the Americans turned to a weapon that had in the past

proved ideal for aggressive assaults on bunkers

and entrenched positions.

The flamethrower.

Fire in warfare is as old as warfare itself

and go all the way back to the use of Greek fire,

all that sort of thing.

So it's not surprising that developers, inventors

and the military themselves started looking at how

to make use of fire or flame.

(soldiers shouting)

First introduced onto the battlefields

of World War II by the Germans in late 1914,

the demoralizing physical and psychological effects

of the new weapon that spewed flames 18 meters

were immediately felt by the allies.

You have two tanks, one tank will hold your gas.

In this case, nitrogen gas,

the other tank will hold your flammable liquid.

The nitrogen gas will drive the petrol down the pipe.

So when you pull the trigger,

you're releasing it an element of the gas,

essentially pushing the petrol out.

As World War II approached,

the basic fundamentals of the World War I design

remained unchanged,

a flammable liquid propelled by a gas.

Although technological advances added to their lethality

by introducing lighter cylinders,

making flamethrowers man portable.

Of course, portable is a subjective term

and the American M1 flamethrower

weighed a sizeable 32 kilograms,

but they proved indispensable in certain situations.

In the main they were used for structures

to suppress bunkers.

Examples of which would be the use of flamethrowers

on Okinawa and coming to shore at Normandy.

While the M1's range was greater

than those of World War 1,

at just 40 meters it involved the operator

exposing most of his body

when engaging suspected entity positions

and the size of the tanks and general stance

of the infantry men using a flamethrower

made for a tempting target.

That carrying it,

what amounts to a flammable bomb on their back.

They're very vulnerable.

Ultimately portable flamethrowers

gave way to tank-mounted flame guns,

which offered better range, protection for the crew

and made for a far more imposing threat,

a threat that would of course be countered.

Little more than a century ago at the Battle of Cambrai,

the world witnessed the first mass attack

by an innovative British weapon

inspired by simple farm machinery.

Despite early examples being slow,

cumbersome and unreliable,

they very quickly developed.

And in less than 20 years,

they had transformed the battlefield.

If it's a straight tank versus infantry unit baffle,

pity the poor infantry men.

However, you can come up with a weapon

that's flexible enough to get it into position

when you need it to put overwhelming force

on one spot on that tank.

Well, that's the goal of the anti-tank role.

By World War II improvements

in the internal combustion engine gave tanks greater speed,

heavier armor, and more lethal weaponry.

The need arose for a mobile weapon

that could put the power to stop them

in the hands of an infantry man.

This war moves fast.

The Germans and Italians found that out in Africa.

We picked up some things too.

The Bazooka.

The famous American bazooka

nicknamed after the musical instrument that it resembled

is a simple tube, the mechanical firing mechanism

sort of like a giant gun,

but it's essentially a guidance tube

or an initial guidance tube for this projectile.

The recoil was balanced

by the countering forces of the projectile

exiting the front of the tube

and the propellant exiting at the rear.

With a pistol grip and shoulder support made of wood,

the unit weighed just six and a half kilograms.

(explosion booming)

And it was easy to operate between a crew of two,

one to load and the other to fire

the 60 millimeter projectile,

which was capable of piercing armor

up to 102 millimeters thick.

Against all German tank types,

often a single well placed shot was all that was needed.

However, success was not guaranteed.

You have the ability to reload,

very important when you're trying to engage tanks,

you might miss the tank.

You might simply damage the tank.

So to be able to find more than one shot,

a reusable system is very useful.

It was such an effective,

portable destructive force that close to 500,000 bazookas

along with over 15 million rockets were produced.

But the Americans were not alone

in looking to put highly destructive capabilities

into the hands of their infantry.

The Cold War era RPG-7

can trace its roots back to the bazooka.

And like it's forebear,

this Soviet system follows the same simple principle

of a reloadable tube

that fires a rocket-propelled projectile.

The differences between the two are in the missile.

It looks like it's got a stick

with a double conical shape on the end of the stick.

When it's launched there are fins that deploy,

they're spring-loaded fins that open up

and that provides strength stabilization

to the weapon system as it flies through the air.

The RPG-7's rocket

is initially thrown clear of the tube

by a booster charge.

Once in motion,

the acceleration sets off a pressure-generated spark

that ignites a sustainer motor,

which accelerates the projectile

once it's 11 meters from the launcher.

By using this two-stage firing mechanism,

the RPG-7 cuts the tube length from 1.5 meters

as it was on the bazooka to just 90 centimeters.

Projectiles up to 93 millimeters in diameter

and four and a half kilograms in weight

are fired at a velocity of 294 meters per second.

And the warhead makes up most of the weight,

which combined with the extra kinetic energy

imparted by the rockets vastly superior speed

means the RPG-7 can penetrate standard armor

as thick as 750 millimeters.

But by far the RPG-7's greatest asset

is its simplicity of construction,

which has seen over 9 million enter service since 1961.

It's prolific,

it's widespread, and the technology is reasonably old,

but it's simple.

Lots of Soviet engineering was simple and effective

and the RPG-7 is no exception.

The RPG-7 uses what is called a shaped charge,

which is lethal against traditional armor.

Suddenly tanks were beatable,

but in modern warfare,

no single machine completely dominates for long.

All weapons develop in response to improvements in others.

The improvements in armor piercing rounds

saw the design tension between armor

and anti-tank weaponry swing in favor of the weapon.

(RPG firing)

With tanks rendered increasingly vulnerable,

designers hit back in the 1970s

with even more sophisticated defense systems.

So one of the ways in which protection

can be offered against something like

your shaped charge weapons systems,

such as an RPG-7 is by using explosive reactive armor.

Explosive reactive armor

consists of sheets or slabs of high explosive

sandwiched between two plates.

When hit by a shaped charge the explosive detonates,

driving the plates apart

and damaging the incoming projectile.

Not so with the munitions fired by the javelin,

which use an ingenious tandem warhead.

The javelin is a guided missile

and it carries on it a shaped charge weapon system.

So where it makes contact with the vehicle,

it detonates the explosive

that propels a high velocity copper jet

into the armor of the vehicle.

A smaller precursor charge

prepares the way for that copper jet

by pushing through the explosive reactive armor

and clearing a path for the larger main warhead

to penetrate the targets primary defenses.

Using a command launch unit

that incorporates an integrated day-night sight,

the missile is thrown free at launch.

And like the RPG-7,

only fires its rocket mortar once clear of the crew.

Engagement of airborne, static

or mobile ground-based targets

is accomplished using either

the traditional direct fire line of sight method

or with help from the missiles inbuilt

infrared guidance system,

which can be programmed to attack armored vehicles

at their weakest point.

It does this by climbing to 150 meters

as it reaches the target

and then rapidly descending from a steep angle

with devastating effect.

Tank armor on its roof

is inherently thin across the board.

So now you've got projectiles

are actually smashing down through the top of tank turrets

rather than trying to penetrate through.

The javelin

is the latest in highly mobile battlefield destruction.

But destruction on a far bigger scale

gets delivered not from on the battlefield,

but rather from above it.

For the first time in man's history,

World War I introduced the concept

of what we now refer to as total war.

And with the entire resources and populations

of the belligerent nations mobilized towards the war effort,

with every human resource

considered a functioning part of the enemy's war machine,

city factories, warehouses and even civilian populations,

not just the military became legitimate targets.

And during World War II,

the rapid development of aircraft,

in particular the long range, heavy bomber

elevated the concept of total war to a new level,

delivering wholesale destruction on entire cities,

the like of which had never been seen before.

On the 14th of March, 1945,

the first of 42 new bombs

were deployed over Germany's industrialized Ruhr Valley.

Officially, they were uninspired designated

as the Bomb, Medium Capacity.

Unofficially, they were called Grand Slam's.

Eight meters long and shaped like an artillery shell,

the Grand Slam's warhead,

which contained 4,000 kilograms of Torpex,

an explosive 50% more powerful than TNT

was detonated after the bomb

had penetrated deep into the earth,

giving a localized earthquake effect

equivalent to 3.7 on the Richter scale.

And the aircraft that carried these massive munitions

was the Avro Lancaster.

When it was designed,

it was supposed to carry about 4,000 pounds of bombs.

The British discovered that in fact,

it was such a strong and robust airframe

that it could carry more.

So they invented the Grand Slam, 22,000 pounds.

That's five times the bomb carrying capacity

than when the aircraft was designed.

The Lancaster was born

of the early war time experience of the Avro Manchester,

a twin engine bomber first flown in 1939.

Within mere months,

it became clear that the all-new Manchester

simply couldn't carry enough bombs far enough.

Avro took the Manchester,

revised the wing,

added four 12 cylinder Rolls-Royce Merlin engines.

And in early 1942, within just 18 months of being conceived,

the Lancaster entered service.

It was one of those examples of an aircraft,

which is designed and which is perfect from the beginning.

So most of the Lancaster's that were built and flown

were Lancaster B1's.

There wasn't a need for many subsequent marks.

It didn't continuously improve.

Using an all-metal construction

that maximize structural strength per weight,

the Lancaster was agile, easy to fly

and capable of withstanding serious levels

of damage in flight.

And the durability of the design

was enhanced by the fact that both the fuselage

and the wings were assembled in modules, five a piece.

But it was quite novel at the time,

but it was built in sections

and that meant that it could be repaired in sections.

So if you came back from Dusseldorf

with a hole in your wing,

the wing was replaced.

It's an example of where the RAF,

indeed the aircraft manufacturers

are adapting their construction methods

to meet the needs of the people who fly this machine

because they always came back damaged.

In all, Lancaster's flew 156,000 operations

and alone dropped over 618,000 tons of bombs over Germany

between 1942 and 1945, destroying entire cities.

And it did persuade the Germans

that the war wasn't happening in Russia or in North Africa,

or Normandy, it was happening in your street.

So the bomber offensive, I think,

was a crucial arm of the British war effort,

especially the British war effort.

And the Lancaster is at the heart of that.

The Lancaster was one of the most

iconic machines of World War II,

a big, slow moving bomber that operated in huge formations.

The Lancaster was not intended to evade enemy defenses

so much as beat them into submission,

but the years after the Second World War

saw a shift in thinking when it came to strategic bombing.

In early 1946, the US Air Force issued a brief

for a strategic bomber that flew above defenses

with the range to carry out missions

independent of bases controlled by other countries.

And so in 1948,

Boeing put their faith in a new engine

and pushed the design envelope

as far as they thought possible.

What emerged from that process

was an aircraft with a wingspan of 56 meters

that would incorporate the two great

aeronautical advances of the time,

the enduring B-52 Stratofortress.

The B-52 bomber used a swept wing design

and it was purely jet engine powered

with a long narrow fuselage,

which was primarily a series of bomb bays

combined with eight engines on the wings.

These advances gave the B-52

an operational range of excess of 14,000 kilometers,

a top speed of 1,047 kilometers per hour

at a service ceiling of 16,000 meters,

which allowed it to launch a strike

from well outside enemy territory.

And its extended range provides it with the capacity

to loiter outside of combat zone

while enemy defenses are subdued and targets are identified.

Most of the lower central fuselage

of the 48 meter long aircraft

is given up to the storage

of a 31 and a half thousand kilogram payload.

With the B-52 capable of carrying

a most astounding array of munitions in its bulky frame.

It was designed at the very beginning of the Cold War

and subsequently has out seen designs

that were supposed to replace it.

So many people thought that it would

no longer be an operation, but it still is.

The B-52 is a great example

of the speed of aircraft development

in the years following World War II.

It boasted five times the payload of the Lancaster,

an aircraft that less than 10 years previous

had been the supreme allied strategic bomber.

And it delivered that destructive force

three times as quickly and four times as far.

It is another example of an aircraft like the Lancaster

that they just managed to get right the first time.

But aircraft development during the Cold War

didn't stop with the B-52.

The combination of cabin pressurization

and jet engine technology

provided bombers like the B-52

with their main defensive capability,

altitude.

At 15,000 meters,

they were able to operate safely

well beyond the range of conventional ground-based

ADI aircraft weapons.

But by the early 1960s,

new radar-guided surface-to-air missiles

had changed the rules yet again.

High altitude bombers suddenly became vulnerable.

To defeat these systems,

general dynamics responded with what was an all new concept,

a long range supersonic bomber

that rather than flying even higher

would evade radar detection

by skimming close to the ground.

The F-111 Aardvark.

The main system that we had to help fly at low altitude

was the terrain following radar.

So this was a forward-looking radar

that actually gave us an interpretation

of the terrain in front.

We could link it in with the autopilot system

on the aircraft such that you would actually fly,

you could fly hands-off

at anywhere from 200 feet to a thousand feet

at any speeds up to 600 knots plus

if you really wanted to go there fast.

That terrain following radar system,

which is standard in most of today's fighter jets

was untried when the F-111 was first flown in 1964

and gave the aircraft unprecedented assault capabilities.

Undeterred by weather or darkness,

the F-111 could enter enemy territory below radar level

and proceed to attack its target at incredible speed.

And it was equipped with two of the most powerful

turbofan engines ever fitted to a production aircraft

that also boasted another technological first,

afterburners.

Basically the afterburner system

is you just pour a whole bunch of fuel

down the back of the engine and the light it up,

and that's pretty much it.

And it just gives you extra thrust.

Commonplace now,

afterburners gave the F-111

extraordinary performance capabilities.

By using those afterburners,

it could climb at close to 8,000 meters per minute

and reach its service ceiling of 20,000 meters

in less than three minutes.

That puts the F-111 in strike fighter class even today.

But despite being designated F for fighter,

the F-111 was a genuine fighter bomber

designed to carry a 13,500 kilogram payload

to create an aircraft that could perform

well under load at low speed,

take off and land from short runways,

and yet still fly it over Mach-2

required another groundbreaking innovation,

variable geometry, or what we know as swing wings.

If you look at the slow speed aircraft,

you'll see that it has a fairly straight sort of fat wing,

a lot easier to generate lift at slower speeds that way.

As you want to go faster,

you actually want to go to more of a Delta shape,

which is predominantly the sort of shape

that you see in high speed aircraft.

And that's where you start sweeping the wings

back to 72 degrees.

The F-111 remained in service

with the US and Australian Air Forces for 30 years.

But like to B-52,

the F-111 was principally designed during the Cold War

to deliver a weapon of such destructive power

that when it was unleashed in 1945,

it changed the planet forever.

In 1939, a letter delivered

by the esteem physicist, Albert Einstein

to the then US, President Franklin D. Roosevelt

resulted in the United States taking a gamble.

As World War II erupted into a destructive global conflict,

Roosevelt ordered the establishment

of the US Uranium Project

to investigate the possibility

of creating a controlled chain reaction.

In June, 1942, the Uranium Project

fell under the control of the US military

and was renamed the Manhattan Project.

And in December of that year,

under a Chicago football stadium,

the world's first controlled nuclear reaction was achieved.

With the war looking more and more

like it would end in an allied defeat,

what followed was the birth

of the single biggest weapons development project

the world had ever seen.

The Manhattan Project that the Americans developed,

which was the scientific and the military

development of these weapons was just enormous.

I mean, literally hundreds of thousands of workers

worked on sites, what 17 sites in 12 states,

huge secret cities built across the US

all feeding into this enterprise.

It was a colossal program.

One team at Los Alamos led by Robert Oppenheimer,

worked on the physics of the bomb.

Huge industrial plants in Tennessee and Washington state

were established to extract the plutonium,

each arm of the massive operation

working in extreme secrecy.

After five years of frenetic research

and billions of dollars on July, the 16th, 1945,

the Manhattan Project came to fruition.

A device was successfully exploded in the New Mexico desert.

With a force of 22 kilotons,

the equivalent of 22,000 tons of TNT,

it dwarfed anything that had come before it.

One of the most profound and moving aspects

of the whole atomic weapon story

is that the men, mostly men,

the men who developed the bomb

were the first to become aware

of what the destructive capacity of the bomb was.

And they debated within themselves

whether or not they should be allowing this to happen.

And I think one of the considerations that swayed them

into regarding this as being justifiable

was that that many of them knew

exactly what they were up against.

Many of them were Jewish refugees from Nazi Germany,

who knew what had happened to Europe's Jews

and knew the costs of not defeating Nazi Germany.

And while the atomic bomb

may have been designed with Germany in mind,

by the time the atomic bomb was completed,

Hitler was gone and the Germans had surrendered,

but the allies were still at war with Japan.

A little after 8:15 AM on the 6th of August, 1945,

the Enola Gay, a heavily modified B-29 bomber

dropped a device measuring just three meters in length,

71 centimeters in diameter and weighing just 4,000 kilograms

over the unsuspecting Japanese city of Hiroshima.

Hiroshima, a manufacturing center of 350,000 people

located about 800 kilometers from Tokyo

had not been randomly selected

as a target for the atomic bomb,

it had been chosen.

Firstly, because up until this point in the war,

unlike Tokyo,

it had been largely unscathed by conventional bombing.

And secondly, because the city was flat.

(airplane roaring) (dramatic music)

The bomb went off,

three and a half kilometers of destruction,

a fireball that big killed probably 80,000 people,

more or less instantly wounded about another 80,000 people.

And because it was a flat site,

the impact of the bomb went for miles and in a circular way

diminishing as it progressed,

but still devastating, utterly destroying the city.

When Little Boy as the bomb was called

detonated 580 meters above the city,

it did so with a force equivalent to 15,000 tons of TNT.

As it exploded,

intense heat rays and radiation

were released in all directions

and almost instantly 13 square kilometers of that city

was transformed into ruins.

And when that city's devastation failed

to elicit a Japanese surrender,

just three days later, a second weapon,

Fat Man was deployed.

But heavy smoke and cloud cover over the city of Kokura

caused a mid-mission diversion to the secondary target,

the port city of Nagasaki.

Not an ideal target from the bomb makers point of view

because it was a hilly, it was in a valley.

And so the blast was constrained,

but even so it killed 40,000 people.

Fat Man had an energy yield

of approximately 22 kilotons of TNT.

And the fireball caused by the explosion

was 280 meters in diameter,

creating a surface temperature

of around 5,000 degrees Celsius.

The role of the two weapons in ending the war

remains the subject of ongoing debate.

Emperor Hirohito's decision to surrender

was also influenced by Russia's invasion of Manchuria

and declaration of war against Japan on August 8th.

But one thing is certain,

the world has never been the same since.

One of the claims that's made

about the use of Little Boy and Fat Man on Japan

was that one of the major reasons for doing it

was not so much to defeat Japan,

but to signal to Russia

that the US had this incredible new capability,

whether that's true or not,

I certainly don't know,

but what is certainly true

is that the creation of atomic weapons

radically changed the global strategic environment.

A change that would lead

to a 40 year period of uncertainty known as the Cold War.

In 1945, there had been just three nuclear weapons

on the planet.

By 1950, there were 304,

299 in the US arsenal and five in the Soviet Union's.

So we entered into the era of the Cold War,

and it was a cold war for a reason,

though there were many hotspots,

the two great powers that were competing

never went to war against each other.

And probably the main reason for that

is the existence of nuclear weapons.

But even a Cold War can be won.

Determined to maintain their lead

in what was now a nuclear arms race,

in October, 1952,

the Americans conducted Operation Ivy

on the Eniwetok Atoll in the Marshall Islands.

The plan was to detonate a device named Mike,

an experiment with a higher yielding form

of nuclear explosion

that derives a significant proportion

of its explosive energy from fusion.

A Thermonuclear device,

Mike was the first of what we now know as a hydrogen bomb.

At 7:15 AM local time on the 31st of October, 1952,

Mike was detonated from a control ship

stationed 55 kilometers away.

The detonation resulted in a massive explosion

equivalent to 500 times the explosive force

of the bomb dropped on Nagasaki just seven years earlier.

Four...

three...

two...

one.

After the test was confirmed to the public,

Time Magazine reported that, "The force and horror

of atomic weapons has entered a new dimension.

The first full-dress, H-blast

turned the mid-Pacific sandspit

named Elugelab into a submarine crater."

And indeed it had.

Elugelab, the atoll on which Mike's detonation took place

was vaporized.

The explosion produced a fireball

six kilometers in diameter

and a mushroom cloud 160 kilometers wide.

Unsurprisingly in 1952,

it was the largest nuclear explosion ever detonated.

And as the tests continued on both sides

and with the development of missiles to deliver warheads,

the numbers of nuclear weapons skyrocketed,

a proliferation to change the nature of warfare.

(explosions booming)

At the heart of the idea of nuclear deterrence

is something called mutually assured destruction or MAD.

And that term is quite literally chose,

the idea is that you would be simply mad

to start a nuclear war

because where the other side had the ability

to wipe you out if you launched against them

and they had the ability to launch

before you could guarantee

that you'd taken out all of their nuclear capabilities

in starting a war,

you would essentially choose to destroy yourself.

In 1955, there were 2,636 warheads

of which the Americans had 2,400.

By 1965, that number had increased to over 35,000

as the US and Russia battled for supremacy.

With enough weapons to destroy the planet

several times over,

an uneasy status quo emerged.

Great powers simply couldn't afford

to go to war with one another.

And that's what nuclear deterrence relies on.

The incredible power of the opposing nuclear forces

means that there are no rational ways

to start a war with one another.

At the height of the third phase

of the Cold War,

the world was home to over 61,000 nuclear weapons.

That number has now dropped to a little over 16,000.

(explosion booming)

But should they ever be used,

mass destruction would result

of a kind that the men of World War I,

a mere 100 years ago could never have imagined.

(dramatic music)