>> Tonight on Frontline... >> PRESIDENT OBAMA: This is an attack on all of humanity and the universal values that we share.

>> In the wake of a series of new attacks... >> Shooting continued across Paris.

>> Two suicide bombers just south of Beirut... >> A two-pound bomb brought down its plane over Sinai... >> As a worldwide coalition struggles with how to fight ISIS, Frontline investigates how they became a global threat.

Tonight, from the ashes of Al Qaeda in Iraq... >> ISIS builds enough strength and the monster grows.

>> Correspondent Martin Smith uncovers the early warnings.

>> ISIS didn‘t become the group that it is today until they went to Syria.

>> The missteps... >> The intelligence analysis continued to point to what could happen.

>> The view was, this is Iraq‘s problem, let them deal with it.

>> And the ancient tribal hatreds that fueled... >> These are not Muslims, and frankly, they‘re barely human beings.

>> "The Rise of ISIS."

>> The last American combat brigade has begun leaving the country.

>> MARTIN SMITH: ISIS began its rise in 2011 as American troops were leaving Iraq.

>> For U.S. soldiers, the war in Iraq has come to an end.

>> SMITH: The country was still extremely volatile.

>> The last U.S. soldier is out of Iraq, other than those... >> SMITH: But Iraq‘s leaders said they were ready to go it alone.

>> History in the making.

>> SMITH: Prime Minister Nouri al Maliki flew to Washington to mark the occasion.

>> It was a moment of optimism.

There was a sense of pride... >> All right, everybody.

>> ...that the occupying forces really left.

And a lot of Iraqis, Sunnis and Shias, were responding positively to that.

>> Today, I‘m proud to welcome Prime Minister Maliki.

>> Both sides presented it as a victory.

Maliki presented it as a great accomplishment-- Iraq would stand on its own two feet.

President Obama talked about this new democratic Iraq.

>> What we have now achieved is an Iraq that is self-governing, that is inclusive, and that has enormous potential.

>> SMITH: President Obama gives a very rosy picture of where things are.

What‘d you think?

>> As somebody who voted for President Obama, I was deeply disappointed because I knew those words were going to go back and haunt him.

>> Thank you very much, everybody.

>> It was at that trip, actually, when things started to go astray.

>> SMITH: What happened was that while he was in Washington, Maliki received a phone call from Baghdad about a terrorist plot implicating his vice president, Tariq al-Hashemi, the most senior Sunni politician in the Shia-led government.

It accused Hashemi‘s bodyguards of planning an attack on Shia targets.

>> We were at the Blair House.

I recall Maliki.

He was fiddling with his phone.

He said, "Well, some guards of Tariq al-Hashemi, "the vice president, have been monitoring our compound.

And they have been arrested."

>> SMITH: Maliki relayed the news to President Obama.

>> l think the President‘s response was, "Well, every country has its own rules, its own law, and the rule of law should be applied."

>> SMITH: How did Maliki interpret what the president told him?

>> I think he interpreted this may be some support of any future actions.

>> The response he got from the president was that this is an internal Iraqi affair.

And that, to Maliki, was a green light in terms of what he can do with the Sunnis, because the United States is not going to stand in his way.

>> SMITH: Maliki returned to Baghdad, and then just one day after the last American soldiers left Iraq... >> Maliki immediately orders that Hashemi be arrested.

>> And it took a lot of people by surprise.

I think that was a departure point.

It showed Maliki is really independent from the Americans.

>> SMITH: Before he could be arrested, Hashemi fled.

He was tried in absentia and sentenced to death.

We interviewed him in Doha, the capital of Qatar.

>> SMITH: Was it possible that your bodyguards were involved in any kind of... >> No way, no way.

>> SMITH: Some of your bodyguards appeared on television.

>> Yes.

I do have plenty of reports of the way that my guards had been treated, unfortunately.

When they just receive brutal torturing, in fact.

>> We‘ll never know what is true because they were held in the Baghdad Brigade headquarters in the green zone.

It‘s been clearly documented over time that torture happened there.

It‘s been documented by Iraq‘s human rights ministry and the Red Cross.

There‘s no doubt torture happened there.

>> SMITH: So the confessions were likely the result of torture?

>> Mm-hmm.

>> SMITH: Hashemi and his bodyguards would just be Maliki‘s first targets.

>> Hundreds of Sunnis had been arrested after the American leaving of the country.

Thousands, in fact.

>> SMITH: In 2012, thousands of Sunnis suspected of subversion were held for months or longer without charges ever being filed.

>> So everyone talk to Maliki that this is not the way of dealing with the people.

This is a discrimination, in fact.

But he is not listening to anyone.

>> SMITH: Many Sunnis didn‘t even make it to jail.

>> The Shia militia were very, very violent.

There were many, many instances in Baghdad and in many other parts of Iraq of Sunnis turning up with a bullet in the back of their head and their hands bound behind them.

This was common.

This was a daily, daily occurrence.

>> SMITH: After the departure of the Americans, more and more Sunnis turned up dead in the streets of Baghdad.

>> The thing to understand about Maliki is that when he looks at Iraq‘s Sunni minority, he sees, you know, Al Qaeda, he sees the Baathists, he sees military coups, he sees plots against him, he sees a population which despises him and wants to come back into power.

>> This is a man who many of his close relatives were secretly arrested and tortured by Saddam‘s regime.

He‘s capable.

And yet if I could use one word to describe Nouri al-Maliki, it‘s "paranoia."

>> He had a deep fear that ultimately, the Baathists were gonna go after him and that he was gonna be targeted and that he would lose power, and it would be the ghost of Saddam Hussein again.

I think that‘s what he worried about.

>> SMITH: Maliki also enraged the tribesmen of the Sunni Awakening.

These were the tribesmen who, in exchange for American money and promises of political inclusion in a new Iraq, had helped defeat Al Qaeda years earlier.

>> I think that he was suspicious of them really, of this force.

They were not sustained or maintained as a potential force that the government might need later on.

>> And then the other key thing was that Sunni leaders in the army and Sunni leaders in the police began to be sidelined, and people with a strong Shia sectarian bent replaced them.

And that meant that a lot of people felt they were being excluded, and that was true-- they were.

(gunfire) >> SMITH: Meanwhile, Al Qaeda in Iraq, the group that would become ISIS, was camped in Iraq‘s western deserts.

It was not much of a force.

The Surge and the Sunni Awakening had severely reduced it.

>> Remember, by the time the Americans left Iraq, the insurgency was broken.

The Sunni insurgency, it was broken.

It was on its last legs.

Al Qaeda had been decimated.

>> SMITH: What remained, though, were the most battle-hardened Al Qaeda militants, a few embittered tribesmen, and some remnants of Saddam‘s Baathist military hoping to regain power.

>> This is a collection of very hardened killers.

These are the guys that the United States didn‘t manage to kill during the war then.

>> These are mostly young men who were in prison, some of them under Maliki.

Some of them were in U.S. prisons.

Mr. Baghdadi, the head of ISIS, was in Camp Bucca.

>> SMITH: After he was released from Bucca, the American-run prison, Abu Bakr al-Baghdadi would, in time, become head of Al Qaeda in Iraq, directing ambushes on Iraqi forces and suicide bombings.

But he had greater ambitions.

In the summer of 2011, he sent a few men into Syria to join the rebels fighting the government of Bashar al-Assad.

(chanting) (explosion) For Baghdadi, the Syrian war was a gift.

>> Suddenly, you have a complete breakdown of the state in Syria.

You have this vast, open space between the two countries.

And so these guys, they‘re suddenly able to find life.

>> ISIS didn‘t become the group that it is today until they went to Syria.

Syria is what made ISIS ISIS.

>> We don‘t know how many Al Qaeda in Iraq guys move from Iraq to Syria in the 2011, 2012 timeframe.

But once they move into Syria, all of a sudden, they‘re able to operate once again.

All of a sudden, they‘re able to recruit once again.

Their message gains traction with the Sunnis of Syria who are looking to wage a civil war against the Shia government.

(explosion) >> SMITH: Al Qaeda was joining the fight along with dozens of other Syrian Sunni rebel groups, but it quickly became a major force.

>> Baghdadi sends a bunch of guys into Syria.

It goes from being nothing to being the most powerful active group.

They‘re running operations all over the country within, like, 12 months.

It‘s extraordinary what happens.

Takes off like fire.

>> SMITH: Back in Iraq, Maliki‘s purges of Sunnis continued.

And Maliki upped the ante in December 2012, when his police rounded up the bodyguards of another prominent Sunni leader, finance minister Rafi al-Essawi.

>> Rafi al-Essawi, everybody loves the guy.

I mean, he‘s greatly respected.

I‘ve seen no evidence that suggested that his bodyguards were doing anything bad.

To the contrary.

And so when his bodyguards are arrested, that I think is the real blow to the Sunni community, because everybody knows Rafi al-Essawi is a peaceful man.

>> SMITH: So you were sitting inside the finance ministry.

>> Yeah, they attacked the office and they took 16 of my bodyguards.

These are almost ten years they are with me.

I‘m sure that they are against terrorism, all of them, almost, they are my close relatives.

>> SMITH: After the arrest warrant is issued for Rafi al-Essawi... >> I called Maliki up.

I said, "What are you doing?

What the hell‘s going on?"

He‘s a colleague of ours.

He was with us yesterday in the cabinet.

And now some police people have gone to arrest him?

This is absolutely unacceptable.

>> Hundreds of thousands of people were very upset because they feel that this is a story of dignity.

No Sunni is exempted.

People started to prepare for a big demonstration in Fallujah and Ramadi.

So I called them, I said to them, "I‘ll join the demonstration."

>> Anyone, Maliki and the gangs of the militias of Maliki, can arrest anyone.

>> I went there.

They are protesting for their rights.

And they have legitimate demands for releasing the innocent people in the prisons, some of these in detention center for two, three, six years without trials.

They are telling us of, in one month or twice in a month, three months, raids in their community and collecting just young people like that.

Collecting people.

>> They were not fully integrated into the security forces as was promised, so they felt, again, completely marginalized.

The idea that it‘s just terrorists, Maliki is trying to cultivate that impression.

No.

The average man in the street, woman in the street, Sunni, perceived it exactly that same way.

>> (chanting) >> SMITH: Officials in the White House saw what was happening.

Obama‘s ambassador to Iraq had warned that Maliki needed to be contained.

>> This was a constant warning that I had made and that others had made before me, that Maliki was a problem.

On the other hand, the president and the country had taken the position, "Iraq was a mistake, we‘ve ended our war "in Iraq.

"If we see things we don‘t like, we‘ll do calls "from the vice president, just like we do with 150 other countries that have similar situations."

>> The Obama administration certainly did tell Prime Minister Maliki and other Iraqis that they wanted to see them play by the democratic rules, that they thought it was a mistake for them to go after their political rivals in this fashion.

But they did it in private.

They didn‘t do it in public.

And they certainly never imposed any kind of a cost.

>> You gotta continue to put pressure on them to do the right thing.

I think everybody just kept their fingers crossed that ultimately, Maliki would somehow step down or be replaced and that Iraq would be in a better place.

>> No, I don‘t think that‘s accurate.

We were engaged with all of Iraq‘s communities.

We were engaged with Prime Minister Maliki, and we were seeking to manage this and press Iraqi leaders to move in a more inclusive direction.

But by definition, our leverage, in order to affect political outcomes inside a very complicated society like Iraq‘s, has inherent limits.

And at the end of the day, it‘s going to be Iraqi leaders who have to make these determinations to work together.

>> (chanting) >> SMITH: As weeks went by, the demonstrations grew.

In Ramadi, protesters camped out on the main road between Baghdad and Jordan, a vital trucking artery.

In other Sunni cities and towns-- Fallujah, Mosul, Tikrit-- other protests halted traffic and commerce.

With youth unemployment running as high as 40%, young men were free to gather.

And support poured in from around the Sunni Arab world to pay for tents, meals and transportation.

One of the principal funders was a wealthy Iraqi businessman living in Jordan, a man with ties to the Baathist regime of Saddam Hussein.

>> SMITH: How much money did you spend in support of those protests?

>> (translated): All that the demonstrations needed.

>> SMITH: And how much was that?

>> (translated): All that was needed.

I don‘t know.

Whatever was needed.

>> SMITH: Khanjar also paid for the establishment of pro-Sunni TV stations.

>> (translated): We encouraged channels like Baghdad, Al-Rafidain and Fallujah to defend our people.

>> (shouting in Arabic) >> (translated): Maliki is the cause of all of this.

He has a problem with the Sunnis.

This is the revolution of the tribes.

I am proud of it and I support it.

>> (chanting): Allahu Akbar!

>> SMITH: 60 miles away in Baghdad, Iraq‘s Shia were organizing their own demonstrations.

Here and in other Shia cities throughout Iraq‘s south, people encouraged Maliki.

>> (chanting) >> They were supporting him.

He was popular in the streets, he was popular in Najaf, he was popular in Basra, he was popular in Babil, popular in Baghdad.

And when he moved against Sunnis, he found himself getting more popular.

So there was no real disincentive at that point to discontinue doing what he was doing.

(explosion) >> SMITH: Back in Syria, Al Qaeda was steadily gaining ground.

In its early months, the group relied on donations from wealthy Sunnis in the region.

>> The Saudis, the Kuwaitis, the Emiratis, all of the gulf states and a whole variety of other countries began to provide support to a whole variety of Sunni opposition groups, and they weren‘t terribly careful about which groups got the aid.

>> SMITH: And soon, Al Qaeda would need fewer donations.

As they gained territory, they would become more self-sustaining, robbing banks, running extortion rackets, seizing Syrian transportation routes and eventually Syrian oil fields.

>> Allahu Akbar!

>> They were very smart.

They understood, "If we can control those oil wells, we‘ll be able to sell the oil on the black market and get cash."

And they went about that in a very conscientious way, field by field.

>> SMITH: In this Al Qaeda video, they are shown planning and then executing an attack on a major Syrian power station.

(gunfire) >> SMITH: U.S.

Ambassador to Syria Robert Ford had urged the administration to quickly provide aid to pro-Western Syrian rebels.

Otherwise, he warned, Al Qaeda would dominate.

>> I think there was certainly warnings from people at my level that in a large, ungoverned space, having Al Qaeda or Al Qaeda-affiliated groups able to operate freely would be as much a risk to the United States as Somalia, Yemen and Afghanistan were.

And in each of those places, the Americans had to act.

>> SMITH: But in Syria, the president chose not to send arms.

>> I think the president‘s concern-- and I respect his decision-- but I think his concern was that ultimately, if we provide those kinds of weapons, we couldn‘t be sure whose hands they might ultimately wind up in.

>> SMITH: You respect his decision.

He was the commander-in-chief.

But you think he was wrong?

>> I think we made the wrong decision in not providing assistance to the rebels.

>> I think President Obama has a fundamental belief that any military action or aiding local fighters will lead to, almost inexorably, 150,000 troops on the ground like Iraq, or 500,000 like Vietnam.

Slippery slope, down the drain, huge disaster for America.

I think he believes that, sincerely.

I think he‘s absolutely wrong.

>> SMITH: You were getting advice from Ambassador Ford, Ambassador Jeffrey in Iraq that we needed to get involved in the Syrian situation, or the Al Qaeda elements that were operating there were going to dominate and become a much more serious issue.

>> Well, let‘s step back here.

I think in the rear-view mirror, people suggest that it was about ISIL.

In those conversations in 2012, it was very much about, "What can we do to effect change as it relates to Bashar al-Assad?"

>> SMITH: Correct, but the urgency increased as Al Qaeda-linked rebels gained more and more power and money.

>> Absolutely, and again, it‘s a complicated picture.

The president was willing to get engaged in support for the opposition in Syria, but he wanted to make clear that we understood there were limits as to how we could solve this problem with our military, and that we had to be very deliberate and careful when it comes to something like providing military assistance to an opposition group.

>> SMITH: Throughout 2012, the president held off.

Without U.S. arms, the more moderate Syrian rebels struggled.

Al Qaeda, meanwhile, was ready to expand back into Iraq.

(explosions) In a campaign called "breaking the walls," they launched a series of attacks on Iraqi prisons.

Al Qaeda‘s ranks swelled with newly freed inmates.

Then in March 2013, a few of Al Qaeda‘s black flags began to appear in the midst of the protests in Ramadi.

And around this time, they started calling themselves the Islamic State in Iraq and al Sham-- ISIS.

Their presence stoked Maliki‘s worst fears.

>> That was a turning point, really.

That was a turning point in the government attitude toward these demonstrations.

"We told you so.

These are infiltrated."

This is the black flag of Al Qaeda.

>> SMITH: Then in April 2013, at a Sunni protest camp in the town of Hawija, there was a confrontation.

>> The facts were a little unclear.

You have some provocateurs, there‘s a police officer who‘s killed-- maybe by Al Qaeda, maybe not-- and Maliki responds massively and with enormous force.

>> No one thought that the Iraqi army can attack demonstrators in Hawija.

They are demonstrating for months at that time, peaceful, calling for the rights.

So when they brought their tanks and the heavy vehicles of the army and the security forces of the ministry of interior and attacked, they killed the people in a very criminal model.

>> It‘s unclear how many people were killed.

The estimates that I‘ve heard from people who saw the bodies was that there were hundreds.

Hundreds and hundreds of bodies.

>> And at that point, ISIS, they were arguing, "You‘re not gonna "get anywhere with peaceful protests.

"You need to have muscle.

You need to use some measure of violence."

And they started to gain more traction with that argument.

>> SMITH: So these are people, young men who sat in those protests in Ramadi and Hawija who decided to take up weapons and join with ISIS?

>> They tried to...

They voted for a new government in Baghdad in 2010.

Their representatives, like Hashemi and Essawi, fellow Sunni Arabs, were purged.

They were humiliated.

They tried to form a region.

They tried to exercise civil disobedience.

They were attacked with Maliki‘s forces.

And so now they‘ve taken up arms.

>> Allahu Akbar!

>> It‘s been called the revolution, it‘s been called the insurgency.

Whatever you want to call it, it was back.

>> If you take Iraq‘s Sunni community, its leadership, it‘s full of reasonable people.

It‘s full of secular, educated, very moderate people.

But they look around and they say, "Where do we go?

"The only people who are gonna protect us are "these really hard guys, and we may not like them, "but we need them because otherwise, there‘s nothing.

"Nobody‘s gonna protect us.

And the Americans aren‘t here anymore."

>> SMITH: Years earlier, the Sunni leadership had warned American officials what would happen if Maliki reneged on the promises of power sharing he‘d made to Iraq‘s Sunnis.

>> The message was, "If we are backed into a corner again, "we will rise up.

"And this time, we will not stop.

"We will take Baghdad.

We will burn it or we will die trying."

(gunfire) >> SMITH: Three months after Hawija, ISIS mounted a spectacular attack right on the outskirts of Baghdad, releasing 500 inmates from Abu Ghraib prison.

>> Abu Ghraib is only seven or eight miles from Baghdad Airport.

It‘s 12 or 14 miles to the city.

So it was very clear that ISIS-led Sunnis, basically, were encroaching and making major, major gains in Anbar Province.

>> It was a huge propaganda win for the Islamic State of Iraq and Syria.

It was basically the prison bust-out was a statement of purpose that, "We‘re here.

"What started after Hawija, in terms of the bombings, "the spike in violence, we‘re orchestrating this, and hell is coming."

>> SMITH: ISIS began bringing more reinforcements over the Syrian border.

It became clear that the Iraqi army could not stop their advance.

In Baghdad, the leadership was worried.

>> I spoke with Maliki.

I said, "Listen, let‘s admit it.

"You cannot do it.

"We cannot do it.

"Our military is dysfunctional.

"And we have an option.

"If our democratic system is threatened, we can go and ask our American friends for help."

>> SMITH: In late October 2013, Maliki would set out hat in hand to Washington.

>> The message was really, "We are under threat.

We don‘t have control over our border with Syria."

And in terms of weapons, Hellfire missiles, you see, we run out of them.

And we warned about the seriousness of the situation, the existential threat that this country is facing.

>> SMITH: But getting American aid beyond Hellfire missiles was going to be a hard sell, in spite of the fact that U.S. intelligence and defense officials were also increasingly alarmed about ISIS.

>> The American intelligence community was saying that this group, the Islamic State in Iraq and Syria, was becoming increasingly potent.

They were expanding their footprint in Syria.

They were expanding their operations in Iraq.

There were months of these kinds of warning signals about the growth and expansion of ISIS.

>> I think the intelligence analysis continued to point to the implications of what was happening in Syria and what could happen in Iraq.

You know, this was not something that people were not being made aware of in terms of the implications.

>> SMITH: The administration did agree to some small increases in military aid.

>> I want to welcome back... >> SMITH: But despite the warnings, the president was not ready to give more.

Maliki wasn‘t seen as a trustworthy partner.

>> SMITH: He was hat-in-hand, asking for more weapons, but the president did not appear to be tough on Maliki at that point, publicly.

Can you tell me that it was different behind closed doors?

>> Yeah, privately.

We said that, "You need not only our security assistance, "you need a political program that all Iraqis can get behind."

>> SMITH: And what did he say?

>> He would commit to do certain things, but there was never the sustained follow-through that was going to be necessary to really have an inclusive Iraqi political culture.

>> SMITH: What leverage could you use with him at that point?

>> Well, we obviously had significant relationships with Iraq.

But at the end of the day, it‘s up to the Iraqi political leadership to govern in an inclusive fashion.

We couldn‘t do it for them when we had troops in Iraq.

We couldn‘t do it for them when we didn‘t.

>> Thank you.

>> SMITH: And after that visit, things got worse.

>> Got much worse.

>> (chanting) >> SMITH: In December 2013, Maliki would strike once again, this time against a hardline Sunni parliamentarian, Ahmed al-Alwani.

>> Ahmed al-Alwani was a Sunni politician, a member of parliament.

He‘d give angry speeches against Maliki‘s government.

>> And Maliki decides that he‘s had enough and the Iraqi forces stage a raid on his house.

(gunfire) Alwani‘s brother is there.

The brother is killed.

Ahmed al-Alwani, the member of parliament, is taken away, but nobody has seen him since.

(gunshots) >> SMITH: After that arrest, Maliki sent the army into Ramadi to tear down the year-old protest camp.

(gunshots) Maliki‘s move would prove disastrous.

>> That provokes a Sunni uprising.

(rapid gunfire) >> The Sunni Arab population of Anbar rose up and said, "Okay, "we‘re sick and tired of you.

"You‘re oppressing us.

Get the troops out of our cities."

>> And the Islamic State takes advantage of that to move inside these cities.

And from there, you have chapter one of the Iraq War of 2014 begin.

(gunfire) >> What happened here is that by virtue of the Shias not opening it up and allowing the Sunnis to participate, that they created the monster that has led to ISIS.

>> SMITH: So they created the monster that they feared.

>> Exactly.

>> SMITH: The fighting lasted only a few days.

In the end, the Iraqi army was no match.

(rapid gunfire) (loud chanting) >> SMITH: You would think this would set off real alarm bells in Washington.

I mean, now you have them taking over a city just a few miles outside of Baghdad.

>> The ISIS attacks on Ramadi and Fallujah certainly did set off some alarm bells in Washington, at least in certain quarters.

But the top-level leadership continued to do virtually nothing.

>> SMITH: Presumably Biden gets on the phone to Maliki?

Or, I mean, what happens?

>> Some phone calls were made.

No question about that.

But of course, the Iraqis had never seen the Obama administration actually take any action either to help them or to hurt them if they didn‘t do what the United States wanted.

>> SMITH: In Iraq‘s north, ISIS was eyeing another target: Mosul, Iraq‘s second largest city.

Months before they attacked, a Kurdish intelligence official gave Iraqi Foreign Minister Zebari a warning.

>> "Tell Maliki I have very, very serious concerns.

"The terrorists have established themselves.

"They have encamped themselves in the western desert "near the Syrian borders.

"And really, they are planning to formally militarily overrun Mosul."

>> SMITH: You took this message to... >> I took this message to him.

It was a clear message of warning.

And he didn‘t take it.

>> SMITH: The White House, too, was warned.

>> The administration not only was warned by everybody back in January, it actually announced that it was going to intensify its support against ISIS with the Iraqi armed forces.

And it did almost nothing.

>> SMITH: Ambassador Jeffrey says that the Obama administration said it was going to speed military assistance, but it did, in his words, "almost nothing."

>> That‘s just not true.

I mean, if you go back and you look at the record of what we were providing to the Iraqis, there was a steady increase, whether you‘re talking about Hellfire missiles, the Apaches, they were held up by Congress.

We sought the expedition of that delivery to the Iraqis.

>> Hellfire missiles started to come.

They increased the intelligence capacity, but it was really not enough, to be honest with you.

I mean, the United States could have done more.

>> SMITH: Then on June 6, 2014, ISIS sent several suicide car bombs into downtown Mosul.

(explosions) (sirens blaring) >> SMITH: ...along with ISIS fighters in pickup trucks.

In some neighborhoods, they were warmly welcomed.

(rapid gunfire) >> SMITH: The Iraqi army, on the other hand, was seen as a Shia militia.

With no local support, the army had deserted by June 10 with barely a fight.

>> They didn‘t know how to respond.

They didn‘t want to respond.

You know, these were people that didn‘t want to do any actual work.

They were fat cats, I call them.

They were people who were earning good money to basically sit at a desk and smoke cigarettes and drink good liquor all day.

>> SMITH: In the end, it took only 800 ISIS militants, with the help of local Baathist military cadres, to secure a city of 1.8 million people.

Even ISIS was surprised.

>> The original intelligence was that ISIS did not come to invade Mosul.

They didn‘t come to take it over.

They came to break a bunch of people out of prison.

But what happens?

They roll into the city and the entire Iraqi army collapses.

And they make some adjustments very quickly, on the spur of the moment, and decide, "Wow, we‘re not gonna just get the prison, we‘re gonna get the whole city."

Then they just keep on rollin‘.

>> SMITH: For ISIS, the spoils included tons of U.S.-made military equipment.

>> I don‘t think bin Laden could‘ve ever dreamt that elements even more radical than his own Al Qaeda would be armed with American M1-A1 tanks or 155-millimeter artillery or up-armored Humvees or MRAPs.

>> SMITH: From Mosul, ISIS rapidly advanced down the Tigris and captured Qayyarah, al Shirqat, Hawijah and Tikrit, the hometown of Saddam Hussein.

There, ISIS was easily able to round up several hundred Iraqi soldiers.

ISIS recorded their execution.

>> SMITH: What did you think when you saw these mass executions taking place?

>> These guys are crazy.

But there‘s method to their madness.

>> SMITH: And what is that method?

>> Control.

I mean, this is one of the first terrorist groups saying, "You know what?

"We‘re not gonna hit and run.

"And we‘re not gonna participate in politics as you know it.

"We actually want to kill everyone who disagree with us, "we want to control the piece of land, and whatever cost it is, we‘re gonna do it."

>> Al Qaeda was an underground organization.

It could hurt.

It could maim.

It could terrorize people, bomb, blow up.

We know their tactics.

But ISIS has a different strategy.

They have a plan.

They have a strategy to establish a state, an Islamic emirate.

>> SMITH: On June 29, ISIS declared a caliphate, an Islamic nation representing the world‘s Muslim faithful-- an entity that recognizes no political borders.

>> As you can see, this is the so-called border.

We don‘t recognize it and we will never recognize it.

>> SMITH: For this ISIS propaganda video, militants bulldozed the Syrian-Iraq border.

An ISIS recruit from Chile is calling on Muslims everywhere to join them.

>> We will break the barrier of Iraq, Jordan, Lebanon, all the countries.

This is the first barrier of many barriers we will break.

>> By declaring the Khalifah, they did something nobody else has done.

>> SMITH: The caliphate.

>> The caliphate.

The implication of this in the minds of the traditional Salafi believers is that they have a religious obligation to pledge loyalty.

>> SMITH: Salafis being hardcore Islamist fundamentalists?

>> I would say the traditional religious fundamentalists.

Due to their faith in that particular sect, they have an obligation to respond to a caliph if he calls them.

Now I know not all Salafis will do that.

But even if one percent of the Salafis do that, you‘re talking about tens of thousands of people now in Nigeria and Saudi Arabia, in Jordan, in every Muslim country, Sunni country.

>> We have chosen to depict ISIS as a successor, or a partner, to Al Qaeda.

It‘s actually not.

Islamic State is a state-building enterprise.

They‘re trying to create a real state, not some post-modern virtual Al-Qaeda-style thing that only exists in your head.

They‘re trying to create something that looks like a real state.

It‘s a very different model.

>> SMITH: On July 4, ISIS made another extraordinary move.

In their newly occupied Mosul, the leader of ISIS, Abu Bakr al-Baghdadi, ascended the pulpit of the Great Mosque.

>> Baghdadi gave a sermon in Mosul.

Bin Laden never did that.

Zawahiri never did that.

>> In an Arab city in broad daylight, an Arab city that used to be under control of American troops?

It‘s a very ostentatious move and one that‘s likely to attract more support.

>> SMITH: After Baghdadi‘s sermon, thousands more jihadists flocked to Syria and Iraq.

>> Virtually every country in the world, you have young, disaffected youth, both men and women, who have little hope in their life, who want to be a part of something special, want to be a part of something successful, and they now see ISIL taking over vast swaths of both Syria and Iraq, succeeding like no one else has succeeded.

This is the Al Qaeda that Osama bin Laden only dreamed of building.

>> SMITH: And unlike Bin Laden‘s Al Qaeda, ISIS fighters operate under the command of experienced military officers.

Several of the top leadership positions are now held by Baathists from Saddam‘s army.

>> What you call ISIS, behind them sit the Baath party and the former regime.

And the Baathists are pretty key to that structure.

I think without the Baathists, it becomes very difficult to pursue ISIS‘s agenda.

You lack a lot of the administrative capability and a lot of the military skills.

>> They know how to emplace artillery.

They know how to use tanks.

They know how to set up defensive positions.

They know how to go on the offensive.

(rapid gunfire) >> SMITH: ISIS military strength was evident when in August, fighters moved into Kurdish territory.

The Kurdish Peshmerga, reputed to be Iraq‘s fiercest fighting force, were easily overrun by ISIS fighters armed with captured American weapons.

Minorities in northern Iraq-- Christians, Shabaks, Turkmen-- faced a stark choice: convert or die, or flee to Kurdistan.

Tens of thousands of Yazidis fled their homes.

Meanwhile, a column of ISIS fighters was approaching Erbil... >> ISIS is advancing closer to Erbil.

>> SMITH: Kurdistan‘s capital.

>> There are some 40 American military advisors there.

>> The United States has a special relationship with Kurdistan.

>> There‘s a U.S. consulate in Erbil... >> Kurdistan is the silver lining of Iraq.

A trillion dollars‘ worth of global energy companies: Total, Chevron, Exxon and Gazprom Neft are invested in Kurdistan.

>> SMITH: It was the threat to Erbil that prompted the U.S. administration to finally intervene.

>> The trigger was the threat to U.S. facilities in Erbil.

That was the start of the air campaign.

>> SMITH: But the U.S. signaled to Iraqis that more assistance would come only if Maliki resigned.

A week later, Maliki stepped aside and the U.S. airstrikes stepped up.

(explosions) ISIS responded by releasing this video.

>> This is James Wright Foley, an American citizen of your country.

>> SMITH: It was just one of many horrific videos they proudly shared.

>> They knew how to use the social media.

They knew how to promote themselves as the only reliable global jihadi movement.

>> The fighting has just begun.

>> You have thousands of foreign fighters who truly believe in this criminal behavior.

>> This kind of bloodlust is psychosis.

There‘s no other word for it.

It‘s not...

I mean there‘s no political program that justifies it.

I think killing is as important to ISIS as securing the caliphate.

But killing first.

>> My fellow Americans, tonight I want to speak to you about what the United States will do with our friends and allies to degrade and ultimately destroy the terrorist group known as ISIL.

>> SMITH: Is ISIS a threat to the United States?

>> ISIS is a threat to the United States.

In the near term, ISIS is an immediate threat to our interests in the Middle East.

There is nothing that would lead us to believe that they would do anything but ethnically cleanse the region and absolutely create a Sunni-Shia civil war.

(rapid gunfire) Long-term, if they achieve the Islamic State that they‘ve declared, then absolutely it will be a threat, initially to Europe, probably, and ultimately to us.

>> SMITH: One week after the president announced he would expand airstrikes into Syria, ISIS besieged the Syrian town of Kobani, right on the Turkish border.

(rapid gunfire) The U.S. attempted to coordinate military help from over 20 countries.

But as U.S.-led coalition airstrikes bombed ISIS positions in Kobani, the Turkish army watched from just over the border, refusing to participate.

>> It‘s a regional issue.

Turkey is a very obvious example.

Which way is Turkey going now?

It comes down to the sectarianism of the area.

So it‘s an issue which Iran and Saudi Arabia have to address, as well.

All those countries really have to get together to say, "Are we prepared to at least shelve our differences "and find a way that we can sort out this dreadful mess that has emerged in Syria and Iraq?"

>> SMITH: Our interventions into this part of the world have not gone well in the past.

So there‘s a lot of people who are going to say, "Look, I mean, I just don‘t see these guys as an immediate, "imminent threat to the United States.

"I don‘t think any good is going to come by us trying to go in there and manage this."

>> I‘d say they‘re right.

We‘re not going to do this by ourselves and we‘re not going to do this for the region.

We‘re not going to have large U.S. forces on the ground to do this.

The only way that you‘re going to solve this problem is if you get the countries and governments of the region invested in it.

>> SMITH: By late August 2014 ISIS was in control of large parts of Syria and Iraq.

The U.S. hoped that Iraq‘s new prime minister, Haider al-Abadi, a Shiite, would get Iraq‘s Sunni tribesmen to once again turn against ISIS.

Without their trust and support, the Iraqi forces cannot win.

>> Without that trust between the Shia and the Sunni in Iraq, without that trust between the leaders of the Sunnis and the leaders of the Shia groups in Iraq, I think you‘re going to create a vacuum that no one will benefit from that vacuum but the extremists.

>> SMITH: Are you an optimist at this point?

>> No, I‘m not an optimist.

I mean, I‘m 41 years in the military and I‘ve spent, as I said, it seems to me, seven or eight of the last 12 years working these very issues in and around Iraq or Afghanistan and wherever else.

This is the right campaign plan, but I‘m pragmatic and every campaign‘s assumptions have to be revisited as the campaign evolves.

And some of these assumptions are actually, I‘ve no doubt, are going to be challenged.

>> This morning, the committee receives testimony from the chairman of the Joint Chiefs of Staff.

>> SMITH: In September 2014, General Dempsey stated that the president may have to reconsider his pledge not to send in U.S. troops.

>> My view at this point is that this coalition is the appropriate way forward.

I believe that will prove true.

But if it fails to be true and if there are threats to the United States, then I, of course, would go back to the president and make a recommendation that may include the use of U.S. military ground forces.

>> SMITH: If General Dempsey does come to the point where he says we need to introduce boots on the ground, will the president reconsider?

>> The president‘s view is that we do not need to do this with U.S. combat forces on the ground.

>> SMITH: I take that as a no?

>> That‘s a no.

Obviously... >> SMITH: Even if Dempsey comes forward and says, "That‘s what we need"?

>> Again, no, in terms of how we are looking at the strategy.

I can‘t anticipate every hypothetical scenario.

But in terms of the strategy itself, the president is very confident and comfortable with a limiting principle as it relates to combat forces on the ground.

>> SMITH: ISIS has now expanded operations well beyond Iraq and Syria.

An American-led military coalition has been trying to defeat them for more than a year.

>> Next time on Frontline... Get ready to change the way you see the game.

>> The brain is riddled with disease.

>> These players come down with dementia and then Alzheimer‘s, and then they‘re gone.

>> Frontline investigates what the NFL knew and when they knew it.

>> The level of denial was just profound.

>> The inside story.

>> You can‘t go against the NFL.

They‘ll squash you.

>> Visit pbs.org/Frontline for more of our ongoing coverage on the reach and rise of ISIS.

>> We will break the barrier of Iraq, Jordan, Lebanon, all the countries.

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