airport in Iraq.

It killed several Iraqi and Iranian military officials, including Iran's top commander

named Qassem Soleimani.

Moments later, Iran's Supreme leader declared Soleimani a martyr and threatened “severe

revenge” against the US.

Over the next few days, hundreds of thousands

of Iranians came out to mourn Soleimani's death.

But Iran wasn't the only place where people took to the streets...

There were demonstrations in

Iraq.

Syria.

Lebanon.

And Yemen.

These are some of the countries where Soleimani commanded a network of powerful militias;

which gave him and Iran extraordinary influence across the region.

This network made him one of the most important people in Iran.

It's also what got him killed.

So how did Soleimani expand Iran's influence?

And what happens to these militias after his death?

It all began with Iran's Islamic revolution.

In 1979, a cleric named Ayatollah Khomeini led a popular movement that toppled Iran's

monarch and established the Islamic Republic of Iran.

This new regime wanted to export their revolution and that threatened countries all over the

Middle East.

Iran was also the first Shia government that billed itself as the preeminent leader of

the Muslim world.

That especially threatened Iran's sunni-dominated neighbors

The first one to act was Iraq.

In 1980, dictator Saddam Hussein sent his army to invade Iran.

Other countries that felt threatened by Iran supported him.

The US sent some weapons to Iran, but mainly supported Iraq throughout the war, hoping

to keep Iran's ambitions in check.

The war carried on for 8 years and nearly a million died.

During that time, Iran was devastated and surrounded by enemies.

So, it devised a strategy to spread its ideology and fight its enemies covertly at the same

time.

But first it needed a security force to find groups to partner with outside of Iran's

borders.

So in the 80s, it put together an elite unit of soldiers and spies, called the Quds Force.

They became a part of Iran's Islamic Revolutionary Guard Corps, a branch of the military that

answered directly to Iran's Supreme Leader.

Next, it needed an opportunity to unleash this force … and it found one in Lebanon.

In the 1970s a civil war was raging in Lebanon.

The US had sent troops as peacekeepers but violence was spilling over into Israel.

So in 1982, Israel invaded Lebanon.

Several Lebanese militias fought back.

Some of these militias were led by Shia clerics, who had ideological ties to Iran.

So Iran sent forces, millions of dollars, and tons of weapons to back their fight.

They eventually merged into one powerful Shia militia called Hezbollah.

They attacked Israeli soldiers in Lebanon and launched rockets over the border into Israel.

Hezbollah even bombed the US embassy and barracks killing 304 people.

Eventually, Hezbollah succeeded.

The US troops left Lebanon in 1984 and Israel pulled out in 2000.

Iran's dual strategy had worked.

It turned Hezbollah into a reliable proxy that could fight Israel and even the US on

its behalf, without inciting conflict on its own borders.

Iran had also found an effective way to export its ideology in Lebanon.

So Iran's Quds Force started supporting proxy militias in Palestine and Iraq.

As it built the foundation for a network, a charismatic soldier worked his way up the ranks...

In 1998, Qassem Soleimani took command of the Quds Force and within a few years he had

an opportunity to firmly establish Iran's influence in Iraq.

In 2003, the US invaded and toppled Saddam Hussein and his Sunni-dominated regime.

This created a power vacuum in Iraq which was quickly filled by Shias.

Solemani used this opportunity to continue to back Shia militias here; growing his network

into a powerful force that fought against the US and other Iraqis.

It became one of the most violent periods in Iraq's troubled history.

Thousands of civilians died, many at the hands of Soleimani's Iraqi militias.

But eventually, a Shia-dominated government took control of Iraq.

Soleimani had managed to solidify Iran's influence in Iraq when another opportunity

arose, this time, in Syria.

in Syria In 2011, protests in Syria turned into a civil

war, which threatened to overthrow dictator Bashar al-Assad.

Suleimani orchestrated a network of proxies to work together to defend Assad.

He called in Hezbollah fighters from Lebanon, Shia-militias from Iraq, and even soldiers

from Iran.

He also created two new militias with Afghan and Pakistani fighters.

All these groups fought alongside the Syrian Army to keep Assad in power.

This intensified a war that eventually killed more than 500,000 people, mostly civilians

and displaced more than 11 million.

But Assad survived.

Soleimani was successfully exploiting conflicts to advance Iran's interests across the region.

And it was making him a very popular figure in Iran.

He became arguably the second most important person in the country.

More conflicts gave Iran more opportunities.

When ISIS sparked another war in Iraq, Suleimani again called on his network to defend Iraq

and keep ISIS away from Iran.

By now, he had unprecedented influence and continued to command the Shia militias in

Iraq directly even after they were officially folded into Iraq's military.

When a civil war erupted in Yemen, Iran threw its support behind a rebel group.

Now instead of being surrounded by enemies, Iran had them surrounded.

Suleimani empowered a vast array of militias across the Middle East...

Many of them are excessively violent, and have killed thousands.

Many are designated terrorist organizations by the US and EU.

And many are corrupt.

Lebanese Hezbollah and the Iraqi shia militias, for instance, are the targets of mass protests

in those countries.

And they're putting down the protests with more violence.

But to Iran and its supporters, Suleimani's a hero.

He helped build a web of militias that not only keeps Iran's enemies in check…

But also provides a pipeline for the Islamic ideology that Iran wanted to see in the far

corners of the Middle East.

It's why Iran's Supreme Leader immediately called Soleimani a martyr and also declared

that his efforts and path won't be stopped after his killing.

Even though its commander is gone, the network remains intact.