Original subtitles

As in the struggle against Nazi Germany,

American strategy in the war against Japan

includes launching mass bombing attacks against factories,

military installations, and cities.

But the map of the Asia-Pacific War

covers enormous distances.

A new, more powerful bomber is needed,

the B-29 Superfortress.

Securing air bases for these super-forts

becomes a primary objective for President Roosevelt

and American military leaders.

All Wars changed the world,

but none of them changed the world

like the second World War did.

Japan's on the march, Germany's on the march.

No-one can imagine the nightmare they're about to unleash,

the most destructive war in human history.

Suddenly the world is turned upside down

and all hell is let loose.

The West is stunned by the speed of the advance.

You get the Allies led by the big three:

Roosevelt, Churchill, Stalin.

Men who are dealing with immensely complicated questions.

It's the biggest military operation of human history.

The Allies have to come together

not just militarily but industrial scale.

It's a global perspective.

They have to fight in every climate

from the Arctic to the jungles of the Pacific

to the deserts of Africa and the depths of the ocean.

But there was no certainty of victory.

It was going to be a horrific bloodbath.

We see humans at their absolute worst,

how they treat other human beings.

And we see them at their absolute best,

willing to give their lives that others might live.

World War II was a struggle in which there could be

one victor and one vanquished.

For over two years,

the United States has been building the B-29 bomber,

the Superfortress.

When it's ready to roll off the assembly line,

the B-29 will be one of the most potent weapons

in the American arsenal.

The B-29 Superfortress

is the most expensive programme in World War II,

$3 billion to go ahead and build an aircraft.

The B-29 is a stunning leap in aircraft technology.

The B-29 will incorporate a pressurised cabin,

airborne radar.

It has 10 miles of wiring.

It had remote-controlled turrets.

It had the most powerful engines in the history of the world.

But the critical thing about the B-29 was range.

It could carry bombs farther, higher, faster

than anything else that had, not just been built,

but ever imagined.

The complexity of its design, however,

delays its manufacture.

It's been riddled with problems.

It ends up behind schedule.

Bombing the Japanese home islands

is a crucial part of the American strategy

in the Asia-Pacific War.

Allied air commanders wanna launch

the same kind of air offensive against Japan

that they've been carrying out against Germany.

They wanna destroy factories, shipyards, infrastructure,

bring the Japanese war economy to its knees.

In addition to strategic considerations,

President Roosevelt understands that the American people

expect retribution against the Japanese.

If you'd have done a public opinion survey of Americans,

there was a palpable sense

of wanting to get these people back for Pearl Harbor.

By 1943, it's payback time.

And so the B-29 is going to become

the first weapon system

that can really attack the Japanese homeland

and military targets.

The problem is, where are your airfields going to be?

They have to be within range of the Japanese home islands.

US Marines have been fighting their way

across the Pacific, but it will take months

before they can secure an area suitable

for launching B-29s.

The B-29's got a 1,600 mile combat range.

So Roosevelt's looking at several options

as to where to base these things.

They don't have an island close enough,

but they do have an ally

within range of the Japanese home islands.

And that ally is Chiang Kai-shek and China.

Chiang Kai-shek emerged as the leader

of the Chinese Nationalist Party in 1928.

He's ruled China ever since.

He is the Generalissimo of China.

He's a general, but he's also a dictator.

The problem he's got is since the early 1930s,

there is rising communism under Mao Zedong.

He's effectively got a civil war.

In addition to internal conflict,

China faces an external threat.

Japan invaded China in 1937

and seized Chiang's capital, Nanking,

as well as all major Chinese coastal cities.

The Japanese control 95% of China's industry,

90% of China's railways, half of China's population.

They control a quarter to a third of China's landmass.

And they closed off all the Chinese ports.

Severed from Chinese port cities,

Chiang established a new capital, Chungking,

and constructed a route that connected China

to the port of Rangoon in the British colony of Burma.

Cut through more than 700 miles of mountainous jungle terrain,

the Burma Road was China's

main route for receiving supplies,

primarily from the United States.

Until Japan seized Burma too.

The final piece of this Japanese imperial puzzle

was the conquest of Burma in 1942.

The Japanese seized the Burma Road

and make it impossible for the Allies

to supply China's armies.

The Chinese have lost their umbilical,

they've lost their artery, all their supplies flowing in.

Chiang Kai-shek has maybe four million men

available for military service, but only a million rifles.

So he's desperate for Western material to flesh out his army

and pose some kind of serious obstacle to the Japanese.

In November of 1943,

President Roosevelt confers with Chiang

and British prime minister Winston Churchill in Cairo.

At the top of the agenda,

how to keep the Chinese in the fight.

Franklin Roosevelt is worried that if China is without resources,

Chiang Kai-shek could make a separate peace with Japan,

which would be hugely problematic for the Americans.

China is where the vast majority of the Japanese army

is currently being tied up.

And let's not forget that Roosevelt

has this big new weapon, the B-29s.

He wants to base them in Southern China.

So keeping China in the war is absolutely essential to FDR.

Chiang goes to Cairo with a big shopping list.

He needs aircraft, fuel, shells, guns.

He'll take anything that the Allies will give him.

He's pretty desperate.

Winston Churchill... This is all a bit alarming to him.

He just doesn't trust Chiang Kai-shek in his bones.

Chiang Kai-shek has a reputation for being corrupt,

not particularly reliable.

There are valid concerns that instead of using the supplies

that FDR is promising Chiang Kai-shek

for the purposes of fighting Japan,

he might instead hoard those supplies

and then use them to fight the communists.

FDR knew he wasn't running a boy scout troop,

so he didn't examine too closely

the morals of those who shared his interests.

That wasn't how you could fight a global war.

At Cairo, FDR and Chiang agree that the Chinese

will build runways for the B-29s

and that the US will send even more supplies to China.

That requires mind-boggling scales of logistics.

For a single bullet to get to a single Chinese rifle,

it's gotta come from a factory, let's say in the Midwest.

So you send it all the way across the Pacific.

The British still hold India,

so it would then get into Calcutta,

then be put onto a train,

then sent up to Northeast India,

and then fly them over the Himalayas

to the nationalists in China.

Flying the India-China ferry

over the highest mountain range in the world

is extremely hazardous.

The men ordered to do it call it the Hump.

Flying supplies into China

is something that's never been attempted on this scale.

These were just transport aircraft,

but the missions were as challenging as bomber raids over Germany.

These aircraft are taking off with incredibly high weights

because we are trying to get as many supplies in as we can.

The route is only about 500 miles,

but the difficulty is the altitude.

These pilots are flying in unpressurised aircraft

over peaks that are 16,000 feet high,

and then back down again to their Chinese bases.

Got this hot, moist air

bubbling out of the Indian Ocean,

meeting with this Siberian air blowing down from Tibet,

causing some of the most difficult weather conditions

on the planet.

You get these incredible changes in air pressure.

Pilots who flew the Hump say

the plane'd lurch 100 feet in the air,

and then drop 200 feet, and lurch back up a 100 feet.

It's hard to imagine for the pilots who do it.

The aircraft is proven but not in these conditions.

So every time they go up, they're learning.

But there's a cost to learning this real time.

594 aircraft are lost and 1,500 aircrew.

The problem is you have to deliver 18 tons of fuel,

and other supplies, to get one ton of stuff to the Chinese army.

It was a trickle of what was needed.

But China remains a priority for President Roosevelt.

There is another option.

The Allies need to reopen the Burma Road.

By late 1943, China has been at war with Japan

for six years, engaging the majority of the Japanese Army.

President Roosevelt and his military leaders

are determined to defend China,

including using B-29s to strike the Japanese home islands.

The US plans to build four air bases around Chengdu

that will accommodate the B-29.

The B-29 Superfortress is a heavy bomber.

And that means it needs a runway

that's strong enough to land on.

But the problem is there's no way to bring in a bulldozer,

or a truck, or heavy equipment into China.

They simply won't fit in the aircraft

that are flying over the Hump.

But the upside for running a bomber campaign out of China

is that the Americans know that they will have access

to all the Chinese labour they could ask for.

Hundreds of thousands of people

grinding out a runway by hand.

No bulldozers or complicated machinery available.

Only manpower and hard work.

Just the sheer scale of human labour,

it looks like ancient history.

Men, women, children, pulling the rollers,

working side by side. Their country in jeopardy,

Chinese civilians defend against the Japanese

any way they can, building roads,

constructing airfields, loading supplies.

China's an agrarian economy

in a time period where industrial warfare has taken over.

So how do they produce all these weapons that you need?

For example, how do you produce tanks?

So part of the problem here for Chiang is that he needs everything.

The only way to bring the tanks and the artillery

that Chiang needs into China

is to reopen the Burma Road.

The Allies have more than a quarter of a million troops

based in Eastern India, from Calcutta to Ledo in Assam.

They plan a two-pronged offensive.

The British 14th Army will push into Central Burma

to expel the Japanese.

An American-led force will cross into Northern Burma

and fight their way through to re-establish the Burma Road.

General Joseph Stilwell commands the American forces.

His personal and professional connection to China

spans three decades.

Joseph Stilwell, well known as Vinegar Joe,

he's cranky, and acerbic, and sarcastic.

But Stilwell speaks and reads Mandarin.

He's a great lover of China

and he has nothing but good things to say about the Chinese.

A respected Commander,

Stilwell has trained thousands of soldiers in his long career.

Stilwell's task is to take a handful of Chinese divisions,

30,000 of Chiang Kai-shek's troops,

and train them up to Western standards.

He takes over an old British POW camp in India

and he's able to give them the training, the weaponry,

so that they turn themselves into relatively solid units.

General William Slim, Uncle Bill to his troops,

leads the British 14th Army, a multinational force

comprised of units from Britain, India, and Africa.

Many have been battling the Japanese

since the invasion of Burma.

Slim says, look, we got beaten in Burma

because we couldn't fight in the jungle like the Japanese can.

They're not superhuman. We have to learn how to do it.

The Japanese were considered to be these amazing jungle fighters.

But we should remember, Japan's not a jungle country.

They're not great jungle fighters cos they grew up in it.

This is about training.

A complete rethink is needed.

Slim starts training everybody, not just frontline infantrymen.

Everyone needs to be able to handle themselves with their weapons,

the bottle washers and the cooks and the truck drivers.

And everyone needs to know that the Japanese

are not these supermen. They're not bogey men.

Actually, they are completely defeatable.

So I think by this point, the war's going very badly for Japan.

You've had the Battle of Midway in 1942,

which Japan lost.

Now, as a result, Japanese shipping

is struggling to get through.

So you've got rationing tightening in Japan.

And then back in Europe, you've had the German loss at Stalingrad.

You've had the toppling of Mussolini.

So I think at this point, Japan doesn't expect

it's gonna get any help, really, from the Axis powers.

Hideki Tojo, who has been Prime Minister since 1941,

is the dominant force in the Japanese government and military.

By early 1944, there's a feeling for Tojo

and for others at the high command

something can be done elsewhere in the war

to try and offer Japan a little bit of progress.

And some kind of dramatic success for the Japanese

might force the Americans to come to the negotiating table.

One idea is to put some pressure on the Allies

in Northeast India and on Chiang Kai-shek in China.

Prime Minister Tojo approves Operation U-Go,

an invasion into India.

His generals prepare to attack

the British bases of the 14th Army

and to capture the American Hump airfields.

Tojo understands that at this point,

these flights across the Hump

are the last remaining connection point with the West

that the Chinese national government has.

And if you can cut those air bases off,

that will then be the straw that breaks the nationalist back.

For the Allies, this is rife with portents of disaster.

March 1944, Operation U-Go begins.

Japanese troops move across the Burmese jungle into India,

toward British bases and the American airfields.

The Japanese commander is General Renya Mutaguchi.

Mutaguchi thinks he is a creature of destiny.

And he's got a plan. He believes that right there,

on the very, very western frontier of the Japanese Empire,

he could strike a blow that could save the war for Japan.

Mutaguchi hopes his invasion

will inspire the Indians to overthrow the British

and join Japan in the war.

The Japanese are banking on speed and surprise,

that they're gonna move three divisions

across these 8,000 foot high mountains

in the space of just a few days.

As such, he cuts the rations for all of his attack soldiers

to just 20 days' worth of food. - The Japanese soldiers

carry a very small amount of food supply, like dried rice.

And they do not carry many heavy weapons.

So the Japanese cannot get locked in

to an attritional battle. Cos they're travelling light,

they're gonna have to rely on capturing British supply dumps

as they go along. It's a gamble.

To get to the air bases in India,

Mutaguchi will need to cross the Imphal Plain,

site of a large British forward base.

The Imphal Plain, it's got like a big river valley,

surrounded by mountainous jungley terrain.

The Brits have used this like a bread basket.

They've got airfields there, they've got supply dumps, food,

everything the Japanese need.

Based in Imphal are three British-Indian divisions

from General Slim's 14th Army.

They're about to push into enemy territory

when they receive reports that Mutaguchi's Japanese troops

are moving towards them.

Bill Slim's new plan is to withdraw slightly,

create a killing zone,

let the Japanese attack through this difficult terrain,

and pound them with artillery and aircraft.

He's going to relinquish ground,

but all the time he's going to attrit,

grind down the Japanese.

This is a high risk strategy

and you can only do that if you're extremely confident

that your men are sufficiently trained.

But Mutaguchi's force arrives quickly

and is far larger than Slim was expecting.

So when these Japanese divisions

start sort of materialising out of the jungle,

it's a real pucker moment for the British.

The Japanese encircle Imphal and cut off its supply roads.

There is this just brutal battle.

The fighting is incredibly close quarter.

And it is absolutely touch and go.

But Mutaguchi is mired in mental models

that were applicable in 1942

but are no longer applicable in '44.

Back then, if you hit an Indian division

in the face with a frontal attack,

a lot of the time it fell apart.

But Slim's army is better trained, it is more resilient,

and from a morale standpoint, they believe in themselves.

They think that they can fight the Japanese toe to toe.

Fighting is relentless around Imphal,

but General Slim has a plan

to bring in reinforcements and supplies.

All this time, Imphal itself is completely cut off.

And if you're gonna make a stand,

you're gonna need supplies.

What Slim recognises with his American colleagues

is that air power is key to the whole thing.

There's only one way to supply this Allied pocket,

and that is by air.

The Americans have already got

a very efficient, well-trained transport air force

in the north of India, the Hump.

And they turn that airlift 90 degrees aside

and aim it towards Imphal and the British troops there.

When you're flying low and slow,

you are one big fat target.

These cargo planes have no defensive armament,

they don't have any guns.

And if you push the cargo out four seconds late,

it's gonna end up in Japanese hands.

But astonishingly it works.

These transports airdrop and land

about 14 million pounds of food, ammunition,

heavy equipment, and thousands of fresh troops.

And that means that Slim can keep his forces fighting.

Mutaguchi had hoped to take Imphal within days,

right off the march. Instead, what he gets is a meat grinder.

For weeks, divisions of General Slim's 14th Army

have been receiving supplies by air.

They're the frontline resisting Japan's invasion of India.

But Mutaguchi's men are running out of time.

The Japanese have gone into the offensive

without much equipment.

They don't have an established supply line.

So every day that they don't achieve success,

it becomes more and more desperate.

Of course, the big problem they face is rations.

They start to run out, hunger starts to become a big issue.

They're picking up snakes, they're trying to eat monkeys.

They are literally starving.

General Tojo famously issued instructions

for the soldiers in the battlefield

that to be taken by enemy as a prisoner of war

is unacceptable.

Facing defeat, they should make a final suicidal charge

and die, or commit suicide.

The survivors are forced to retreat.

Japanese soldiers are dropping dead along the route.

The retreat becomes hellish.

The Japanese words were translated as the road of bones.

The survivors' accounts are of mass suicides

all along the way.

There are stories of Japanese buddies getting together

and hugging each other

and then detonating a grenade between the two of them.

Up to this point in the war,

this is the largest defeat the Japanese Army

has ever suffered on the ground, around 60,000 casualties.

Mutaguchi had a vision of this operation

to destroy the Allied efforts in Northeastern India

and foment an insurrection.

All of those dreams are shattered at the end of this.

In the spring of 1944,

President Roosevelt is focused on Operation Overlord,

the upcoming invasion of Normandy.

But he's frustrated by the delays in East Asia

and the fact that the B-29s are still not in action.

America is in Burma and in this theatre

to supply China with weapons

and to supply their B-29 bases in Southern China.

Roosevelt has been told time and again by his military men

that they're devoting precious resources

on an effort that looks increasingly futile.

And yet Roosevelt simply doesn't see another horse to back.

In May of 1944, there is no alternate place

from which B-29 bombers can operate.

In Northern Burma, General Vinegar Joe Stilwell

is preparing troops to push to the Burma Road.

If the Americans can reopen that road,

it's gonna completely transform

not only the ground campaign in China for Chiang

but also the aerial campaign for the American B-29s

that are gonna be based in China,

because they will be able to drive over the heavy equipment

that they can't fly across the Hump,

like steam shovels and steam rollers.

And so it'll transform these bases into the sort of bases

that Americans like to build,

big, sprawling, and full of warehouses.

Stilwell's plan is to move across Northern Burma,

attack the Japanese military base at Myitkyina,

then push forward to create a new route to the Burma Road.

He sent 7,000 men, including Chinese troops,

and a veteran American deep penetration force

nicknamed Merrill's Marauders,

on a three-week march through the jungle towards Myitkyina.

Certain fighting environments kill you

all by themselves. You don't need bullets, you don't need shells.

The jungle kills you.

It destroys armies day by day.

The American and Chinese troops inserted there,

they're just absolutely devastated by illness.

They've all got amoebic dysentery, severe diarrhoea.

They've all got, you know, dengue and other tropical fevers.

There was nowhere to rest, there was nowhere to recuperate,

and nowhere to get the resources for war.

On May 17th, Stilwell's troops

launched the attack on Myitkyina.

It's a hard-fought battle.

There's more Japanese than expected.

And the Japanese fight doggedly for it.

The Americans call in air support

from their bases in India.

And take Myitkyina Airfield.

US gliders land,

bringing reinforcements...

...and General Stilwell.

So with the fall of Myitkyina,

that now enables the Americans to play their strong suit,

which is construction.

Army engineers and local labourers

start to build a new route from India to the Burma Road.

It's hundreds of miles long,

scraped out of the jungle,

and it's a major construction programme.

It's gonna take months.

From the British and American standpoint,

it's all looking good.

It's gonna take a while to rebuild that road,

but we can rebuild it now.

And it seems that the tea leaves are now propitious

for a B-29 offensive out of China.

The problem is that the Allies don't know

that the Japanese have

an even bigger land operation up their sleeve.

General Stilwell's victory at Myitkyina

will enable the Americans to reconnect to the Burma Road.

But it's a slow and arduous process

and the road won't be operational for months.

In June, 1944,

B-29s begin to arrive at the airfields in China.

The Army Air Forces have been waiting

for the B-29 for years.

Finally, here they are,

ready to fly their first missions out of China.

The idea is to put up

a sustained bombing campaign over Japan.

And the key is being able to fly missions

over and over and over again.

The problem is logistics.

The B-29 is an enormous fuel hog.

It runs on about 9,000 gallons of gasoline per sortie.

They also need a lot of bombs.

The only way you're gonna get bombs

and fuel to those airfields is they gotta fly over the Hump,

until they open up a new Burma Road.

It takes eight airlift missions

flying over the Hump for every B-29 combat mission

just to bring in the bombs and the fuel.

In mid-June, the first B-29 combat mission to Japan

sets off from Chengdu.

68 Superfortresses

attack the Imperial iron and steelworks

at Yawata in Southern Japan.

But because they don't have enough supplies

coming into China, they're only flying a few missions at a time.

It's just not going to add up

to the sustained pounding campaign that Roosevelt wants.

Meanwhile, Prime Minister Tojo

has launched an offensive in China.

It's called Operation Ichi-Go,

which means Operation Number One.

And this is the largest operation

that the Japanese undertake during the war.

The offensive has two goals,

secure land access to Japan's occupied possessions

in Southeast Asia

and capture US air bases in China.

The Japanese attack

with about a half a million troops,

several thousand artillery pieces,

hundreds of tanks, a lot of aircraft as well.

The big surprise of this campaign

is how poor Chiang Kai-shek's forces are.

At this point, some of them are starving.

There've been lots of deserters from their army.

And with that level of morale,

some of these forces, under Japanese pressure,

simply melt away.

The Japanese push south,

overpowering Chinese forces.

Millions of Chinese attempt to flee,

caught between a foreign invader

and their own corrupt leaders.

The US is forced to abandon bases and airfields.

It's a huge embarrassment for Chiang Kai-shek,

particularly in the face of his allies.

All this time, he's been trying to talk up what he's capable of

if only the Americans give him what he needs.

And yet in the face of Operation Ichi-Go,

his forces just seem to crumble.

For the Americans looking at the wreckage

of the aftermath of Ichi-Go,

they recognise that the Chinese can't defend American bases

no matter where they are.

On top of that, the increasing logistical headaches

of trying to get supplies over the Hump

means that they decide to just cut their losses.

And they pack up those B-29s.

The Army Air Forces have put everything

into making these Chinese bases work,

but they're done with China.

And the Americans may now have a new option

for basing B-29s, which is a better option.

Since 1943,

American forces have been fighting their way

across the Central Pacific.

Now a combined Marine and Army force

is on the verge of invading the Mariana Islands,

Tinian, Guam, and Saipan, only 1,600 miles from Japan.

So if the Americans can capture the Marianas,

the B-29 bomber will now be within range

of almost all of Japan.

The expectation for the Americans is that this should be

a relatively easy operation,

but the reality is gonna be utterly different.

Just after D-Day, the Allied invasion of Europe,

American forces attack Saipan in the middle of the Pacific.

This is really an unprecedented display

of American power projection,

that the Americans are able to launch

these two massive operations,

Overlord first in Europe and then Saipan.

They're separated by half a planet.

They're thousands of miles apart.

The expectation is that this is gonna take three days

for two Marine divisions and an Army division

to be able to conquer Saipan.

But the Japanese had fortified it

and built D-Day style fortifications,

not only bunkers and pillboxes,

but they had dummy bunkers and pillboxes

so that they could waste some of the naval bombardment

on fake targets.

In fact, there's actually 32,000 Japanese there.

Saipan is part of the Japanese defences

that they would consider to be the inner ring

that must be defended,

that they will sacrifice the most for.

Because if they lose Saipan, then Tokyo is in danger,

and that's where the Emperor is.

The resistance is ferocious.

The Americans successfully get

a full division's worth of troops on there

within the space of just a few hours.

In the initial assault, 8,000 Marines land.

Over 2,000 of them become casualties.

This is a bloodletting beyond what anybody had expected.

Any time a Japanese formation

attempts to put in a counter-attack,

they are immediately met

with inordinate amounts of naval gunfire

that just crushed them.

The Japanese retreat into the hills in the interior,

along with several thousand Japanese settlers

living in Saipan. And they forced the Marines and the Army troops

to root them out of caves in these hills.

The battle for Saipan lasts almost a month.

Thousands of civilians die, caught in the crossfire.

The final climax of this battle happens at a set of cliffs

on the northern part of the island.

At Marpi Point, advancing US troops

trap civilians and Japanese soldiers

between the frontline and the sea.

The Japanese propaganda

that's been fed to these people

tells them that the Americans are going to kill all the men,

rape all the women, and it's effective. They don't surrender.

And then as the Marines close in,

some of them leap to their deaths,

some of them clutching their children.

Marines and soldiers confront the inconceivable.

For Japan, the loss of Saipan is a disaster.

They've had the heart

ripped out of their defensive line.

And they know that the Americans now

are gonna have perfect operating conditions

to launch this bomber offensive against Japan itself.

The casualties are high, for both sides.

But the terrible loss of life

finally gives the B-29s

the air bases they need to bomb Japan.

Instead of having hand-built runways in China

that require airlift just to bring in the gas,

now in the Mariana's islands, you have huge runways

built by the Seabees using brilliant white coral,

as hard and durable as you can want.

On these three islands,

Saipan, Tinian, and Guam,

the Americans build five long runway complexes,

each to be supported by a bomber group of 180 B-29s.

And suddenly the Marianas

are the world's biggest air base.

FDR's objective, the B-29,

finally gets its optimum opportunity to achieve the mission

for which it was developed in the first place.

November, 1944,

B-29 Superfortresses

take off for the first of many missions

to bomb the home islands of Japan.

With the capture of the Mariana island chain,

the United States is capable of regularly striking Japan,

just as it's been able to hit Germany

for the past two years.

As the tide turns for these Axis partners,

each country tightens its grip on its people.

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