nuclear missiles that could be launched at a few minutes notice.

Now, one of the technical challenges they had to overcome that you might not think of

is acoustics.

Launching a missile in such a confined silo generates

a loud sound, so loud that it would've shaken apart the missiles

before they could even launch.

So the walls of the inside of the silo had to be covered

in acoustically absorbent tiles,

very similar to those in the world's quietest room.

But after all of the technical challenges were sorted,

what I wanted to know was 'how could they have launched these missiles

very quickly, if needed, but also never by accident?'

So I visited one of these Titan missile silos in the Arizona desert

to find out exactly what it would have taken to launch a nuclear missile.

Well, Derek this is level 2 of the silo, we are down some 10 meters below the surface now.

And this...

is the launch duct.

— Wow. — And that is Titan II.

The largest and most powerful missile weapons system ever deployed by the United States.

And what kind of bomb is in there?

That is a thermonuclear bomb.

It is a 9 megaton weapon.

Compared to Hiroshima?

Oh, call it 650 times.

An enormously powerful weapon.

And what was the idea with it?

The idea behind Titan II was to instill enough fear in the mind of the enemy,

to cause them to think twice about launching an attack against us.

Knowing that 10 meters below the desert in our fortified concrete bunker,

we could ride out their first strike, and live to retaliate, if we're forced to do that,

the consequences for the enemy would be so unspeakably horrible

that maybe they would prefer not to get into it with us in the first place.

That's the essence of deterrence.

This missile is no longer active, but the launch system is preserved.

And I wanted an insight into how it felt to control this incredible power.

Can we go launch one?

I thought you'd never ask!

There were 54 of these silos, each one staffed 24 hours a day, 7 days a week.

Ready to launch their missiles on the exclusive order of the President of the United States.

Alright then, have a seat here Commander.

Thank you.

So, this is the control center, this is where the crew waited to launch the missile.

And how do we know when we need to launch?

[Speaker beeping]

On radio: 'Alpha, 2, 3, Charlie, Hotel, Victor' (A23CHV)

So, we're going to write down every letter and number that we hear in a form in this notebook.

I'm going to write it down in this notebook.

We'll compare each other's work. If we agree that we've copied the message correctly,

then we have what's called a 'valid message,'

and authorization to take our lock off the big red safe.

You know your combination, I know mine, we don't know each other,

so we both have to agree to get inside.

Inside we find authenticator cards.

I'll give those to you.

In the secret message, they sent us a seven-character code word.

We're going to look at the first two letters of the code word, we're going to find the authenticator

that has those first two letters.

If the card here matches the code word they sent us, then this is a legitimate order to go.

That gives us permission to put in our launch keys. I've already put them in for us.

Key right here for you, commander. And for me there's a key right over here.

The keys are far enough apart that not even a long-armed guy like me can reach them both.

The keys must be turned within 2 seconds of each other

and held, they're spring loaded,

so held for 5 seconds to start the launch.

That guarantees that two people will be required to do it.

You just can't run back and forth and do it yourself.

And last but not least, we need the secret unlock code for the missle.

Six little wheels. Each little wheel has 16 letters of the alphabet.

Nominally 17 million combinations.

Only one will operate the missile.

This is the fail safe that prevents an unauthorized or accidental launch of the missle.

So once we have all those things: authentication, keys, code, we're good to go.

— All set? — Let's do it.

Give me a countdown, "3-2-1 Turn keys", we'll send this thing on it's way.

After you comander.

3...

2...

1...

Turn keys.

And hold.

Okay, you may release.

That's all there is to it.

The green light turns on. Its says "Launch enable".

For all intents and purposes, that should say "Welcome to World War III"

Because that's pretty much what it boils down to.

When you turn the key you are committed. There is no "Oops" switch anywhere.

When the batteries come to full power, the missile will transfer to internal power,

meaning that it is fully independent.

About that same time, the silo door starts to slide open.

It will slide through security radar beams and set off the alarm.

That gives us "Silo Soft".

"Guidance Go" means the internal guidance computer has full control of the mission.

In a few seconds we'll have main engine start.

From engine start we will build up thrust.

Pump the hold down bolts.

And off you go.

Into the wild we know.

So that's it? We just basically just ended life on Earth.

As you know it.

In these silos, the Titan missiles had a terrifying purpose.

But they were also put to much better uses, minus their war-head of course.

For example, the Voyager spacecraft was launched into space atop a Titan III missile.

And Neil Armstrong took his first flight into space atop a Titan II.

The exact same missile that would have delivered nuclear warheads to the Soviet Union.

So the Cold War didn't only bring us this fear and potential of mutually assured destruction,

it also made space exploration possible.

Now I want to say thank you to everyone for writing in to request that this documentary be played in your area.

Thanks to you, we've managed to get it broadcast in Norway, Sweden and the Middle East.

And details are in the description, so check it out.

For everyone else, the documentray will be available online via our broadcasters

though there may be some geo-blocking restrictions.

But I'm pretty confident that anyone who wants to see the documentary will be able to via those means.

So I hope you watch it, I hope you enjoy it. It premiers in just a few days in the US.

That's July 28th: 10pm Eastern, 9 Central.

For more details check out links in the description.

I hope you check it out and I really hope you enjoy it. I appreciate so much your support.

It means everything to me. So again, thanks for watching.