The Syrian Democratic Forces, a US-backed group of Kurdish and Arab fighters, announced on Saturday that it had captured the last territory held by the group.
"Syrian Democratic Forces declare total elimination of so-called caliphate and 100 percent territorial defeat of ISIS," said Mustafa Bali, a spokesman for group.
"On this unique day, we commemorate thousands of martyrs whose efforts made the victory possible," he added.
But although the terror group may no longer control territory, many questions about its future remain.
Does this mean Isis is finished once and for all?
Absolutely not. The vast territory that Isis once held earned it massive wealth and helped spread its terror on a grand scale, but even without it the group remains a potent threat. It is already carrying out attacks in areas that were previously “liberated” from its control.
In Iraq, it is following much the same pattern it did during its rapid rise to power: kidnappings, assassinations, and roadside ambushes aimed at intimidating locals and restoring its extortion rackets.
In Syria too, attacks are an almost daily occurrence. James Jeffrey, the US Special Representative for Syria, said recently that Washington believes there are “between 15,000 and 20,000 Daesh armed adherents active, although many are in sleeper cells, in Syria and in Iraq.”
The Syrian Democratic Forces have said that a continued US presence in the country is essential to ensure the enduring defeat of Isis there. But Donald Trump has already announced his intention to withdraw all of the 2,000 US troops stationed there. The president later walked back on that decision, saying that a few hundred troops would stay. But Washington’s long term plans for stopping the rebirth of Isis are unclear.
There are also no signs that the Isis ideology, which brought thousands of Muslims from across the world and won it followers among the downtrodden of Iraq and Syria, has been truly defeated. Many people fleeing from the last Isis-held territory, including women and children, still proclaimed their loyalty to the group. Both countries are far from a recovery, and the conditions that gave rise to Isis in the first place still exist in both.
Nevertheless, the collapse of the physical caliphate marks a significant ideological and military setback for the world’s most powerful jihadist group.
How was Isis defeated?
The fight to defeat the caliphate brought together the bitterest of enemies, and cost tens of thousands of lives.
By the end, the terror group could count among its battlefield opponents two military superpowers in the US and Russia, along with the Syrian army, the Syrian armed opposition, the Kurdish-led Syrian Democratic Forces, the Kurdish Peshmerga, the Kurdistan Workers’ Party (PKK) the Iraqi army, a number of Iraqi Shia militias, Turkey and a global coalition of some 70 countries.
The battle was not always coordinated between these powers, but it is a sign of the brutality of Isis that they all found common cause to fight it.
In 2014, the group carried out one of its worst atrocities when it overran the town of Sinjar in northern Iraq. The town and the surrounding area is the traditional homeland of people from the Yazidi faith, whom Isis considers heretics. Isis fighters slaughtered thousands of civilians and took thousands of women as sex slaves. The UN would later categorise the attacks as a genocide.
That terrible crime, and the threat it posed to other areas of Iraq, prompted the US to intervene against Isis. In August 2014, as thousands of Yazidi civilians were surrounded by Isis fighters, the US launched the first airstrikes against the group.
It would be the first action in a long US-led coalition involvement that would prove decisive in defeating the Isis caliphate. Over the next few years, thousands of coalition airstrikes — most the vast majority of which were carried out by the US — would clear the path for local forces on the ground in Iraq and Syria to recapture ground from Isis. The coalition carried out more than 30,000 airstrikes across both countries. But while they were extremely effective, this tactic left a trail of destruction. The cities of Mosul and Raqqa, and many others, still lie in ruins.
The toll on civilians was staggering. Airwars, an independent organisation that tracks casualties casualties caused by the US-led air campaign, estimates that as many as 12,000 civilians were killed in the bombardment. Local sources indicate the number could be as high as 30,000.
How did Isis get so powerful in the first place?
Isis was born in the chaos of the US invasion of Iraq. It began as an offshoot of Al Qaeda, and later changed its name to Islamic State in Iraq in 2006.
The group gained valuable battlefield experience fighting US forces there, and counted former Saddam Hussein-era military leaders in its ranks.
The outbreak of civil war in Syria in 2011 provided the group with an opportunity to expand. Abu Bakr al-Baghdadi, the Isis leader, began sending operatives across the border from 2011 to set up a Syrian branch.
In 2013, Baghdadi’s organisation broke with Al Qaeda, and set out on its own path. Foreigners from around the world flocked to Syria to join the group, attracted by its extremist ideology and promises of an Islamic state for all Muslims.
Its experienced fighters made rapid gains against the Syrian government and other rival rebel groups. By as early as 2012, it had taken control of major oil fields in eastern Syria, giving it an important source of revenue.
In 2014, Isis made its move in Iraq, which was dealing with a crisis of its own. The Shia government of Prime Minister Nouri al-Maliki was seen as brutal and sectarian by the country’s Sunni population. Maliki purged the country’s leadership of Sunni representation, and locked up thousands on charges of terrorism.
All of this created fertile ground for Isis. When it finally decided to emerge from the shadows in 2014, many Sunnis saw it as the lesser of two evils.
The group used blitzkrieg tactics to storm major Iraqi towns and cities like Mosul, Fallujah and Tikrit. The Iraqi army was ill-prepared, and fled with much of a fight. In doing so, they left behind masses of military equipment — humvees, weapons and ammunition — that was put to use by Isis.
Oil, extortion and “taxation” of the massive population under its control allowed Isis to generate annual revenues of around £2 billion. That gave the group enormous staying power.
Is Isis still a threat to the UK and other countries around the world?
Yes. Thousands of former Isis fighters who joined the group from countries around the world are thought to have returned back to their countries.
Alex Younger, the head of MI6, recently said that surviving foreign Isis members seeking to return home will present a major security challenge in the years ahead.
"They are likely to have acquired both the skills and connections that make them potentially very dangerous and also experienced extreme radicalisation,” he said.
“That fact needs to be uppermost in our minds as we approach this admittedly extremely complex and difficult problem. Public safety is the first thing that we will consider.”
Research by The Soufan Centre earlier this year found that at least 425 British Isis members have so far returned to the UK – the largest cohort in Europe.
But many have “disappeared” from the view of security services, who will not publicly confirm how many returnees have been jailed or are being tracked.
But the group’s followers needn’t have travelled to Syria to be a threat. One of the Islamic State’s biggest strength is its ability to inspire attacks in its name from followers who may only have communicated with it online.
It has carried out hundreds of attacks in more than 30 countries since 2014, killing thousands.
Jane’s Terrorism and Insurgency Centre called Isis the “the deadliest worldwide in terms of the number of non-militant fatalities caused” in its report on terror in 2018.
The group has also extended its franchise outside of Iraq and Syria. According to the Counter Extremism Project, the group has declared wilayat (provinces) in Iraq, Syria, Egypt, Libya, Algeria, Yemen Saudi Arabia,Nigeria, Afghanistan, Pakistan, and the North Caucasus.
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