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CARL AZUZ: Welcome to CNN 10.

I'm Carl Azuz.

It's great to see you this Thursday.

International relations are the key factor

in today's first story.

It concerns the civil war in Yemen

that ramped up four years ago.

It's torn apart the Middle Eastern country.

This isn't a simple battle between Yemeni

government forces and a rebel group

that wants a new government.

That might have been how it started,

but terrorist groups, like ISIS and al-Qaeda,

are believed to be operating in Yemen.

A famine has struck the country, civilians are starving,

and the war has become international.

Saudi Arabia is leading a group of nations that are

attacking the rebels in Yemen.

And Iran is believed to be supporting those rebels.

The United States is not directly involved in Yemen,

but it has given military support

to Saudi Arabia and its allies.

A recent CNN investigation accused Saudi Arabia

of providing some American weapons and equipment

to militias in Yemen.

This would break the rules of America's arm sales

to Saudi Arabia, according to the US Department of Defense.

But the top US commander in the Middle East

says it wouldn't be a good idea for America to stop

supporting the Saudi-led group.

There is a close relationship between the US

and Saudi Arabia, and it goes back more than half a century.

- The s of Saudi Arabia and the United States

are two unexpected allies.

One's an autocracy, the other a democracy.

There are many differences between the two.

But one thing they have in common

is that each country has what the other wants.

Saudi Arabia has oil, and the United States has arms.

To understand how reciprocal the relationship is,

we need to go back to how it started.

Saudi Arabia, as we know it, was founded

in 1932 by King Abdul Aziz.

A few years later, oil was struck,

and American companies, sensing an opportunity, moved in.

ANDREAS KRIEG: It was a relationship, which

was based on the company--

Standard Oil-- in the name of the US government

trying to look for access to oil resources.

- This picture shows where the relationship crystallized.

This was Saudi Arabia's founder King Abdul Aziz meeting

US President Franklin Roosevelt on the USS Quincy

on the Suez Canal in 1945.

ANDREAS KRIEG: The United States wanted to have a secure access

to the oil resources.

And at the same time, they would provide

the Saudi kingdom with access to arms

and obviously provide protection.

- As the years past, the relationship strengthened.

Standard Oil founded Aramco, the Arabian American oil

company, which controlled every oil well

and barrel in the country.

And as the oil flowed into the US,

American made arms flowed into the kingdom.

Between 1950 and 2017, Saudi Arabia

bought more than $100 billion worth of arms from the US,

making the kingdom the country's biggest customer.

It's a relationship so strong that even when

Saudi Arabia and the US are on opposite sides of an issue,

arms continue to flow.

For example, in 1973 and the start of the Yom Kippur War,

Egypt and Syria launched a surprise

offensive against Israel.

The US responded supporting Israel, which Saudi opposed.

The kingdom and its OPEC allies responded

by setting an oil embargo, reducing

production, and significantly impacting the US economy.

But there was no slowdown in arms sales.

PIETER WEZEMAN: If we look at the actual figures of arms

supplies to Saudi Arabia from the US,

we do see that that was around the time

that you really see a very significant increase

in those arms supplies, which then

continued over the decades.

And partly this may also be related to the fact

that that really was the moment that oil prices

really increased very rapidly.

- Even 9/11-- where 15 out of the 19 attackers were Saudi--

did little to rattle the arms relationship

with the kingdom, which has denied

any involvement in the attacks.

PIETER WEZEMAN: Around 2005, there

was a dip of volume of deliveries of weapons

from the US to Saudi Arabia.

But I think that didn't necessarily

have to do with 9/11.

I think it had more to do with the fact

that Saudi Arabia didn't have the best financial conditions

at that time and that it had already

stocked up on a very large quantity of advanced arms.

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- And in 2017, US President Donald Trump's

first foreign visit was to Saudi Arabia,

where he signed an arms deal said to be worth $110 billion.

PIETER WEZEMAN: For a long time, Saudi Arabia hasn't really

used its equipment very much.

But that then started to change in 2015.

We see the, let's say, the full scale military intervention

by Saudi Arabia in Yemen.

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- The Yemen conflict has become the world's

worst humanitarian crisis, with tens of thousands killed.

It's also widely seen as a proxy war between Iran and Saudi

Arabia, with Houthi rebels supported

by Iran and pro-government forces supported

by the Saudi-led coalition.

The world has changed a lot since the relationship between

Saudi Arabia and the USA began.

Imports of oil from the kingdom to the US

have dropped by 47% since a high in 1991.

Since that first accord in 1932, Saudi Arabia

has had seven kings.

The US has had 14 presidents.

But through it all, the bond between these two nations

has remained unbreakable.

CARL AZUZ: 10 second trivia--

which of these places is located the farthest north?

Anchorage, Alaska, USA, St. Petersburg, Russia, Reykjavik,

Iceland, or Oslo, Norway?

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The northernmost city on this list,

at 64 degrees north latitude, is the capital of Iceland.

But they're all latitudes north of 55 degrees, which

means their smartphone maps could be affected by a shift

in the Magnetic North Pole.

There's the True North Pole and the Magnetic North.

The True North pole is geographic.

It's the northernmost point on the planet.

The Magnetic North Pole is where compass needles point.

Historically, it's been located in the Canadian arctic,

several hundred miles away from the True North.

And it's moving.

Scientists say it's always done that slowly.

But in recent years, the Magnetic North Pole

has been speeding up, traveling about 34 miles per year

in the direction of Russia.

Why is this happening?

No one knows for sure.

Many scientists think it's because the Earth's

magnetic field is tied to a liquid outer core

deep inside the planet.

When the liquid flows, it could pull

the Magnetic North with it?

Will compasses still point north?

For the most part, they will.

But this could cause some navigational trouble

above 55 degrees north latitude, so

for people who live in the cities mentioned

in the 10 second trivia.

What can be done about it?

Well, there's something called the World Magnetic Model.

It keeps track of the Earth's magnetic poles,

and it's used by militaries, North

American and European countries, and civilian navigation

systems.

Officials usually updated every five years,

so it can stay accurate.

But they just took steps to update it sooner than that,

so it can keep up with the faster moving Magnetic North.

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Superhero crime fighters have always had a way

to shoot a rope or a web around people

who are trying to get away.

Now that kind of technology is becoming available

to real-life crime fighters.

This thing is called the BolaWrap.

It's not considered a deadly weapon.

But it uses a blank charge to fire an 8-foot rope

toward a suspect.

And its makers say it's effective as long

as that suspect is between 10 and 25

feet away from the officer.

Suspects would then get tied up, roped in, wrapped up, tethered

tight, fastened down, knotted up, cinched in, bound together,

hamstrung, or leashed up.

They probably wouldn't get away.

I'm Carl Azuz, totally tongue-tied for CNN.

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