NARRATOR: They're watching you.
More than 6,000 satellites circle the Earth.
Every day, they uncover new, mysterious phenomena
that defy explanation.
Ghost ship of the Bermuda Triangle.
It came, from what we can tell, out of thin air.
NARRATOR: Vietnam's vanishing cipher.
SZULGIT: Given the history of this star,
maybe it's not surprising it's been destroyed.
NARRATOR: And the hills that changed history.
It's really incredible how this changed
the world in such profound ways.
NARRATOR: Baffling phenomena, mysteries from space.
What on Earth are they?
[theme music playing]
February 13, 2020.
Satellites track Storm Dennis,
a 90 mile-per-hour cyclone, as it moves
eastward across the Atlantic Ocean towards Ireland.
RUBEN: Storm Dennis was one of
the most massive cyclones ever recorded.
It battered this region of the world.
NARRATOR: On Monday, February 17th, the sky is clear,
and in County Cork on Ireland's southern coastline,
aerial images uncover a mystery.
There is this huge vessel, like, marooned on the land.
It's enormous.
CAVELL: This is a significant ship,
and clearly, something horrendous has gone on here.
NARRATOR: The ship, measuring around 250 feet
stern to bow, has appeared overnight.
Further, aerial footage reveals no signs of life on board.
What's really weird is that nobody seems to
know where this ship came from.
It came, from what we can tell, out of thin air.
CAVELL: What happened is a mystery.
She's been abandoned, left to wash up
on the Irish coast as a ghost ship.
NARRATOR: Lured by the ghost ship,
urban explorer Harry Gallagher is hiking along this
remote stretch of coastline to study it up close.
-After what, 2.5 hours? -MAN: Yeah.
I think it's around that corner.
I'm not gonna lie. I see a storm coming.
Okay, let's -- let's go. Let's go forward.
NARRATOR: As the storm gathers,
Gallagher navigates 40-foot-high cliffs to reach the ship.
Oh, my God! Full-blown snowstorm,
and look at what we're doing.
NARRATOR: The ship is often under surveillance from
local authorities, so Gallagher must work fast.
[Gallagher breathing heavily]
[Gallagher grunting]
Oh!
I'm gonna explore this boat quickly,
because the tide is coming in.
NARRATOR: Gallagher's footage yields vital clues
to the vessel's identity.
When you look closely, you can see that this ship
was the MV Alta,
which has been missing since 2018.
NARRATOR: According to maritime records,
the 2,300-ton-ship is built in Norway in 1976.
Its subsequent voyages are shrouded in mystery.
Tracking the path of the ship is really
hard to do, because it turned off the GPS.
But the last place it was known
to be is near the Bermuda Triangle.
Now we have a real mystery on our hands.
Why would the captain turn off
this essential piece of navigation equipment near
probably the single most infamous
stretch of water in the world?
NARRATOR: Over the years, dozens of vessels have
disappeared in the 500,000-square-mile
Bermuda Triangle.
The ship's records could explain why the captain
turned off satellite tracking
during its voyage towards this patch of ocean.
CAVELL: MV Alta has gone through
a lot of name changes since she was launched,
and this tends to be an indication that
she might have been engaged in some illicit practices.
NARRATOR: The ship's last confirmed journey
begins in September 2018,
when it leaves Greece bearing for the Caribbean.
A month later, it makes a series of
strange looping movements before being intercepted
by the U.S. Coast Guard
southeast of the Bermuda Triangle.
Some reports suggest the crew was stuck on board the ship for
three weeks before rescue came.
The crew were in a desperate state
by the time they were rescued,
They were running out of food, and the ship was abandoned.
NARRATOR: The ship's cargo and fate
following its abandonment remain unclear.
Gallagher searches below deck for clues.
GALLAGHER: Let's go down into the depths.
It's pretty much just completely empty.
This is so weird.
CAVELL: The fact that this ship has been stripped
tends to suggest that pirates might have got ahold of her,
boarded her, taken what they wanted,
and just let her drift on.
NARRATOR: Some experts suggest that pirate attacks
could explain the disappearance of other ships in
and around the Bermuda Triangle.
Historically, Bermuda is a hub of piracy.
A. MORGAN: So maybe the ship was attacked by pirates.
That still doesn't explain how it gets
all the way to the coast of Ireland.
NARRATOR: Over a period of 17 months,
the ghost ship travels 2,300 miles.
Ocean currents are the key to deciphering its epic journey.
Ocean currents are still very much a force that scientists
don't understand as much as we'd like to.
A lot of the planet's surface is covered with water,
and that water is in constant motion.
That motion is hardly random.
NARRATOR: The movement of our oceans is dominated
by five rotating bodies of water
called gyres and thousands of secondary currents.
They are driven by factors such as the Earth's rotation,
landmasses, and wind patterns.
AUERBACH: We're looking at the ocean,
and all we see is the surface.
But underneath that surface is this immensely
complex system that stretches, literally, for miles down.
NARRATOR: Under the surface is a kind of
aquatic conveyor belt called thermohaline circulation,
which causes differences in temperature and salinity
in the deep ocean.
Using satellite images, supercomputers are helping to
discover how it carries
ghost ships across vast distances of open ocean.
While we're making big advances in our
mathematical modeling,
it's critical to have physical examples like this ghost ship
to help explain how these ocean currents work.
NARRATOR: Decoding our currents could help
identify the path and fate of countless
other lost vessels and perhaps even those claimed by
the Bermuda Triangle itself.
Until then, the ship remains wrecked on Ireland's shores,
disintegrating into the waters that carried it there.
It's really amazing to think about the power
of the open ocean and of currents and just
what they can do to even really large vessels at sea.
NARRATOR: Coming up, eaten by the jungle.
It's really odd.
It's like it's been deliberately erased.
NARRATOR: And the haunted isle.
It's a reminder of this really
horrifying moment in American history.
NARRATOR: Over the past six decades,
satellites have mapped the ever-changing surface
of our planet in incredible detail.
Satellite images are an extraordinary
tool for scientists and historians.
They basically let us travel back in time.
NARRATOR: When analysts scan images taken 20 years apart
above southwest Vietnam, they uncover a mystery.
MUNOZ: That's probably one of the strangest things I've seen.
There's this star pattern just kind
of sitting in a patch of wilderness, but...
if we look at more recent images,
the star is completely gone.
SZULGIT: It's really odd.
It's like it's been deliberately erased from history.
NARRATOR: Investigators turn to historic records
of the region for clues.
They reveal something intriguing.
Given the history of this star,
maybe it's not surprising it's been destroyed.
It's a reminder of one of
the bloodiest periods of the 20th century.
NARRATOR: That period begins on March 8th, 1965,
when, after years of simmering tensions,
the U.S. deploys the first of millions of troops to Vietnam.
Despite superior numbers and firepower,
they soon incur huge losses at the hands
of their communist adversaries.
One of the major reasons why the U.S. failed in Vietnam
was that the American military was designed for kind of
traditional warfare and these pitched battles.
AUERBACH: Vietnam was a different type of conflict.
A lot of it was fought in small unit actions.
It was fought with irregular forces.
It was a type of war that
they weren't really trained to fight.
NARRATOR: The Viet Cong use guerilla tactics,
perfected during their wars
with the French in the 1940s, to devastate U.S. morale.
They then melt back into the jungles that cover almost
half of the country,
often making pursuit all but impossible.
MUNOZ: The Americans weren't just fighting the Viet Cong,
they were also fighting the environment.
The jungle was an incredibly harsh place to wage
a war, unless you had grown up in that jungle
the way the Viet Cong did.
NARRATOR: The Viet Cong's successes mean Washington
deploys increasing numbers of special forces
into the conflict.
One of their objectives is to halt the spread
of enemy influence and propaganda
among the local population.
America was aware that the Viet Cong were
recruiting South Vietnamese villagers into their forces.
So the special forces were running a counter program.
WALTERS: Rather than letting these people
get recruited by the Viet Cong,
the idea was to teach them guerilla warfare tactics
that had been used so effectively
against the Americans.
NARRATOR: Devised by the CIA in 1961, the Civilian
Irregular Defense Group program, or CIDG,
trains local villagers
into a combat-ready paramilitary force.
You could have a small special forces team,
and under their command,
300, 400, 500 local troops,
who knew the ground better than the Americans.
AUERBACH: That type of counterinsurgency,
what they would call now asymmetrical warfare,
would actually become one of
the dominant forms of war fighting in the future.
NARRATOR: To train the recruits,
special forces set up a fortified base at
the site in the image, near the Cambodian border.
It replicates a star fort,
a defensive design first used during the 15th century.
The two shapes in the image basically represent
two perimeters, designed to prevent
the Viet Cong from overrunning the place.
This type of fortress had projecting bastions.
So anybody who tried to attack the fort would have
been confronted by fire
on both sides, and that would have been lethal for them.
NARRATOR: By 1968, special forces have used the camp
and others like it to recruit and train more than
42,000 local paramilitaries.
The success of the so-called Hamlet Militia
incurs the wrath of the Viet Cong,
who, nine months later, launch a raid on the fort.
This particular camp was actually attacked in 1968
at nighttime and was subjected
to repeated assaults using artillery action.
WALTERS: The base was bombarded for hours on end,
and following that,
you then have waves of Viet Cong soldiers attacking
NARRATOR: 145 Vietnamese soldiers die during the attack,
some of the estimated 3.8 million people
who lost their lives during the war.
The fort goes on to survive the conflict,
but around a decade ago,
local authorities remove almost all evidence of it.
Today, like the bodies of many of those who died here,
the remnants of the base have been claimed by the jungle.
MUNOZ: The base itself might not exist anymore,
but through historical photos,
we can kind of gain a glimpse into this really painful part
of U.S. and Vietnamese history.
NARRATOR: Coming up, the invention
that transformed the world.
RUBEN: It's easy to forget how important the invention is,
but so many other advances depended on it.
NARRATOR: And countdown to disaster.
It was the deadliest storm in American history.
NARRATOR: October 24, 2021.
Eyes in the sky flying above the region
of Ayrshire, Scotland, capture something
in the countryside below.
AUERBACH: What we see in this image is a series of what looks
like pits or mounds, and they're scattered
all across this one area.
It's almost like chicken pox or giant
moles have dug up from under the ground -- it's weird.
NARRATOR: Around 50 of the bizarre markings
litter the area.
BELLINGER: It's a strange image.
It doesn't seem to be any
rhyme or reason to where they're placed.
NARRATOR: Dialing up the magnification
reveals crucial details.
Zooming in, each one of these mounds has
a dark, what appears to be a hole, at the top.
What we could be looking at here are mineshafts.
JANULIS: The question is, if this is a mine,
what were they mining,
and why don't we see any infrastructure around them?
NARRATOR: Local historic records confirm that
the pockmarked mounds are the remains of mines,
ones that helped change the course of human endeavor.
Ayrshire was absolutely critical in the Scottish
Industrial Revolution,
which, in many ways, led the world in industrialization.
NARRATOR: Beginning in Britain in the mid-1700s,
the Industrial Revolution is the most important period in
human history since the domestication of animals
15,000 years ago.
The economy explodes, with wealth
doubling every five decades.
The Industrial Revolution was a time of
tremendous technological,
economic, and geopolitical change.
This period changed many aspects of
life and work beyond all recognition.
NARRATOR: Scottish engineers and scientists play
a vital role in this revolution.
They include James Watt, whose steam engine
transforms industry and transportation around the world.
Even though Scotland is a relatively small
country, nonetheless,
its contribution to the global Industrial Revolution
was very significant.
SZULGIT: Scotland underwent this dramatic shift from a mostly
underdeveloped rural country
to one of the key heavy manufacturing hubs of
the British Empire.
NARRATOR: When prospectors discover coal near the site in
the image, the local economy explodes.
It's part of a mining boom, which
sees production nationwide increased by over 1,000 percent.
Coal here is of high quality,
but it was also realized that it could
be converted into a valuable material called tar.
NARRATOR: Tar occurs naturally, but the discovery
that it can be produced from coal
fuels a massive increase in its use during
the Industrial Revolution.
AUERBACH: Tar is particularly valuable as
a sealant to make things waterproof.
So you're going to use it to seal up buildings,
but most importantly,
you're going to use it to seal up ships.
[ship whistle blows]
NARRATOR: Tar is vital to Scotland's
River Clyde shipyards,
which, between the 19th and 20th centuries,
manufacture over 30,000 vessels,
20 percent of the world's total.
To produce it,
workers must first excavate vast amounts of
coal using a process called bell pit extraction.
The scars in the satellite image are created by digging
down into the earth and depositing the soil that you
displace all around the hole, and once you hit the vein,
you chase it in whatever direction it goes.
NARRATOR: Tar is produced as a byproduct when
the coal is superheated in giant kilns around the mines.
BELLINGER: This was brutal, hot work.
Accidents would happen, and they could be deadly.
NARRATOR: One of the workers at the site in
the image is a man called John Macadam.
In 1820, he has an idea that will change the world.
Now, that name might sound familiar, because Macadam was
an entrepreneur in road building,
and he's the guy that introduced Macadamization.
NARRATOR: Macadamization uses layers of
crushed stone packed down with
heavy rollers to create durable,
smooth road surfaces.
It means tracks in use since Roman times can be
transformed into ones capable of carrying heavy machinery
long distances.
It's easy to forget how important the invention is.
But so many other advances depended on it.
With the addition of tar, Macadam's
surfaces can support multiple 1,000-pound vehicles.
It means that car ownership in the U.S. alone
rockets from a few thousand in 1900 to over eight million
just 20 years later.
You'd think that the roads came after the cars,
but it's actually the other way around.
RUBEN: With paved roads, you could ride heavier vehicles.
Industry could thrive, because different materials could
be transported from one place to another.
NARRATOR: 200 years after Macadam worked
at the site in the image,
it remains a testament to his genius,
revealed from the skies.
It's really incredible how we can look down
from space on this series of events
that happened so long ago that changed the world in
such profound ways.
NARRATOR: Coming up, the Alamo of the Pacific.
CAVELL: It's extraordinary that the men there were
able to hold out for that long.
NARRATOR: And the giant underwater waffle.
I haven't seen anything like it. It's incredible.
NARRATOR: March 19, 2020.
A satellite flying 400 miles above the Philippines
scans a strange land mass in the waters below.
MUNOZ: Looking at the island,
one of the things that really jumps
out at you the most is how it's shaped.
WALTERS: It's got this really kind of large head at
the front, and then it's followed by this long tail.
I mean, it looks like a tadpole.
This is Corregidor,
a 1,235-acre island located
close to the Philippine capital, Manila,
and its shape isn't the only weird thing about it.
This island is really highly forested,
and yet, near the center,
there's a clearing,
and in that clearing is a huge building.
It's not clear who would go through the trouble of
building something in the middle of the jungle
in the center of this tiny island.
NARRATOR: Sascha Auerbach studies
the 1,500-foot-long structure in more detail.
It's very regular, and it seems to be subdivided into sections.
It also looks pretty solid,
like maybe fortifications of some sort.
NARRATOR: Historic records confirm this site
was once a vast military fortification,
one whose history charts some of
the darkest events of the 20th century.
The story of this structure is
one of the grimmest tales to emerge
from the Pacific Theatre in the Second World War.
NARRATOR: In the hours following its attack on Pearl Harbor,
Japan launches a coordinated assault on the Philippines,
including on U.S. forces based there.
M. MORGAN: They came in the form of bombing raids,
and then ultimately, a large-scale amphibious
landing operation.
CAVELL: The garrison in the Philippines was completely
surprised when it was attacked on December 8th.
They were not prepared to be hit with this kind of strength.
NARRATOR: As Japanese forces advance towards Manila,
they outmaneuver and outgun the 135,000
U.S. and local troops.
NARRATOR: On December 23, 1941,
General Douglas MacArthur gives the order to
abandon the capital and retreat to the structure in
the image.
The Japanese have the island surrounded.
You have American troops on Corregidor completely
cut off from being reinforced or being resupplied.
NARRATOR: Over the following five months,
the Japanese subject Corregidor
to a series of ferocious aerial attacks.
As the siege goes on,
you have American soldiers getting more and more desperate.
I mean, they've got no food, and now
you're starting to get malaria spreading through the base.
CAVELL: It's extraordinary that the men there were
able to hold out for that long.
They're surviving on monkeys and lizards that they can
catch from the jungle,
and there are no reinforcements coming in to relieve them.
They are in a really terrible position.
For all intents and purposes,
the military base at Corregidor ended up being
the Alamo for the Americans in the Pacific.
NARRATOR: On May 6, 1942,
with 1,000 troops in desperate need of
medical attention, the garrison surrenders.
The man really had nothing left to give.
There was just no way to mount a resistance to
the overwhelming Japanese force that was poised
to land on the island.
NARRATOR: The siege costs the lives of
800 U.S. and Filipino soldiers.
But for the survivors, the nightmare has only just begun.
The large surrender of Philippine and U.S. forces
at the end of the Corregidor campaign
would produce this horrible postscript.
CAVELL: When they are captured,
they are at the mercy of the imperial Japanese army,
and that is not a place you want to be.
NARRATOR: In April 1942, the Japanese
forcibly transfers 76,000 soldiers
roughly 65 miles across the mainland
to a concentration camp.
It becomes known as the Bataan Death March.
These soldiers were already in pretty poor shape.
Some of them were very ill -- as they walked,
they began to drop out of line, and anyone who dropped
out of line, who stopped marching,
was immediately shot or beheaded.
NARRATOR: The six-day march claims
the lives of around 11,000 prisoners of war.
The Japanese kind of sowed the seeds
of their own destruction with this cruelty.
Because when news of the Bataan Death March
reached the U.S. public,
it really fired people up
and recommitted them to the war effort.
NARRATOR: Three years later,
U.S. troops gain revenge when they storm
Corregidor and recapture the garrison in the image.
Today, it stands as a crumbling memorial
to all who died here, visible from space.
It's a kind of dark reminder, if you like,
of this really horrifying moment in American history.
NARRATOR: Coming up, the day terror came to Texas.
The loss of life is really catastrophic.
NARRATOR: And the 17-mile-high spy.
This is a really revolutionary
form of warfare on the battlefield.
NARRATOR: Spring 2019.
Satellites above Galveston Island off the coast of Texas
find something lurking in the water.
BROWN: We're looking at the Gulf of Mexico,
and there is what seems to be
this sort of waffle-shaped structure.
I haven't seen anything like it.
NARRATOR: The mystery structure covers over
half a square mile of marshland.
This grid formation is enormous.
It dominates the landscape.
NARRATOR: It turns out that the weird structures
are the legacy of an historic event,
which decimated this region of Texas
more than a century ago.
What we're looking at is a modern attempt to
try and protect the island from a catastrophic disaster.
NARRATOR: That disaster begins in August 1900,
when meteorologists track
a massive storm approaching the Texas coast.
Despite its ferocity, authorities don't alert
the residents of Galveston's until it's too late.
It was a catastrophic blow to that community.
The hurricane of 1900 ends up
being the deadliest storm in American history.
NARRATOR: On September 8th, 135-mile-per-hour winds
rip into Galveston,
dragging a 15-foot-high wall of water in its wake.
The city of Galveston is sitting almost at sea level.
So when the hurricane hits, it's devastating.
The waves were high enough to flood the entire town.
NARRATOR: Footage captured by inventor Thomas Edison's
film company reveals that the colossal wave
obliterates almost 4,000 buildings.
Around 8,000 people die,
more than four times as many
as those killed during Hurricane Katrina.
The loss of life that happens as a result
of the flooding and the storm surge is really catastrophic.
There were so many dead bodies that they simply
dug huge trenches and put bodies in those trenches
and then covered them up.
Before the hurricane, Galveston was a booming place.
After the storm, it really struggles to recover.
NARRATOR: In the aftermath, authorities begin work
on a more than 100-million-dollar project
to protect Galveston from future hurricanes.
Alongside constructing a giant seawall,
workers use over a million trucks worth of sand to lift
the entire city 17 feet above sea level.
This is just an immense engineering project
that allows the entire island
to be raised higher than it was before the storm.
When you've been through something that horrific,
it's no wonder that you're building whatever you
can to protect yourself from ever experiencing it again.
NARRATOR: Yet what protects Galveston
isn't just the height of the island,
but the marshlands in the image,
which form a barrier against storm surges and flooding.
Marshlands are one of
the best defenses against storms and hurricanes.
So the more marshlands that we have,
the longer those islands are going to be able to exist.
NARRATOR: During the 20th century,
coastal erosion reduces
the amount of marshland around Galveston by 90 percent.
Ad the number and intensity
of hurricanes in the region increases.
One of the problems with barrier islands like
Galveston is that they're primarily sand,
and so they erode pretty easily.
NARRATOR: The concrete grid in the image
is part of an ingenious attempt
to reverse this process and protect the city's more than
50,000 inhabitants.
This grid is to create a protected lagoon, where marsh
plants can regrow and spread
all over this area, and so provide a natural defense
against any future storm surge.
This image is part of the effort to make sure that
nothing like the Galveston hurricane ever happens again.
NARRATOR: A natural defense against the fury
of Mother Nature, revealed from space.
This is one of the greatest examples of
the ways in which we have attempted to control
our environment -- it's incredible.
NARRATOR: Coming up, an unidentified floating object.
This remote discernible pattern,
it's kind of like a dog chasing its tail.
NARRATOR: Every day, 24 GPS satellites
complete two orbits of the Earth,
transmitting data vital to 21st century life.
The incredible amounts of data they produce
are being utilized in countless ways,
everything from tracking vehicles to global mapping
to keeping the most accurate clocks in the world
actually running on time.
NARRATOR: In May 2021, a series of satellite signals
captured off the Pacific Coast of the United States
baffles analysts.
We're looking at the Pacific Ocean here,
and I'm seeing this GPS data that's obviously
tracking something.
But what is it tracking?
I mean, this thing is all over the place.
MUNOZ: There's really no discernible pattern.
It's kind of like a dog chasing its tail.
NARRATOR: The data tracks something moving around
a 37,000-square-mile area between Santa Barbara
and Tijuana, Mexico.
My first thought is that this
must be some kind of ocean creature.
A. MORGAN: There aren't a lot of creatures that would
be capable of traveling a distance like this.
It would have to be really big,
something like a gray whale.
NARRATOR: Every year,
thousands of gray whales travel through these
Pacific waters in search of mating grounds.
Their migrations cover over 16,000 miles,
the longest of any marine mammal.
Climate change is interfering with whales'
migration patterns -- as the temperature
of the water increases, whales get confused.
So it wouldn't be unusual for
biologists to want to track gray whales.
NARRATOR: However, closer analysis shows
that whatever the satellite is tracking,
it can't be marine in origin.
If you look, you can see that this pattern is
not just over the sea but also over the land.
A. MORGAN: So it seems more likely that
whatever it is we're following is airborne.
NARRATOR: Intelligence reports
state the satellite is tracing the flight
path of a revolutionary new piece of technology
called a Thunderhead Balloon.
The Thunderhead Balloon can conduct intelligence,
surveillance, and reconnaissance
operations at the stratospheric level,
which means they are extremely high altitude spy balloons.
NARRATOR: Thunderheads are the latest iteration
in a long line of reconnaissance balloons,
which stretches back more than 150 years.
The U.S. first deploy one in 1861, when the Union Army
uses it to survey a Confederate camp
near Fort Monroe, Virginia.
The balloon had the capability of observing troop movements as
much as 15 or 20 miles away,
so it could function as a very effective
early warning system.
WALTERS: This is a really revolutionary form of warfare,
because you suddenly got an aerial presence
on the battlefield.
NARRATOR: Today, the Civil War's primitive hydrogen
balloons have evolved into
solar-powered autonomous vehicles monitored from space.
One of the key advantages of
the balloons is their long stay time.
They can stay over the target for a long time to
do reconnaissance.
Secondly, because they don't require any fuel, all the space
you would use for fuel,
you can fill that with any number of
surveillance equipment.
NARRATOR: Thunderheads can also maintain their shape,
despite changes in atmospheric pressure.
This enables them to carry payloads
to altitudes of over 17 miles.
These balloons make a great vehicle for reconnaissance,
because wherever you float them,
they're too high up to be shot down.
MUNOZ: The primary mission for systems like
the Thunderhead Balloon has always been
surveillance and reconnaissance,
but now there's some consideration being given to
turn them into actual weapons.
NARRATOR: Loitering munitions are ones positioned high above
a target for long periods of time, evading detection.
Military chiefs then carefully select high-value targets
before launching drones carrying missiles or bombs
attached to the balloons.
It's a flying remote control bomb that can stay in the air
for as long as you like,
until the person you want to take out pops his head out.
NARRATOR: Autonomous balloons like Thunderheads could
also potentially be used
for even more devastating aerial attacks.
The Air Force is looking at the concept of
attaching a group of drones to one of these balloons,
flying it over to an area that
they need to either surveil or potentially attack.
MUNOZ: So if you carry 10 or 12,
you could hit 10 or 12 individual targets.
You multiply your combat effectiveness
by employing these kinds of weapons.
NARRATOR: The exact nature of the tests
captured off the U.S. coast remains a mystery -- for now,
all observers can do is watch the skies.
These balloons have raised some eyebrows over
civil liberties.
If they can just hover there and watch what's going on,
what's to say they couldn't spy on our own citizens?