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If Hitler isn't defeated, it's the end of the free world.
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Hello, I'm Asde Moshiri from the BBC World Service.
This is the global story.
As Syrians celebrate the fall of Bashar Al Assad, another group is watching developments with keen interest.
The jihadist group calling itself Islamic State the last time Assad's power was challenged, is filled the vacuum it paralyzes its enemies with terror.
We're coming for you, he says with disturbing calm, with men who love death as much as you love life.
At their peak in 2014, the jihadists wrought terror over 8 million people across Syria and Iraq and built the so called caliphate.
They'd been longing for humiliation, then execution.
That's the fate the enemies of Islamic.
State know they face if they're defeated or captured.
The battle to claw back territory from IS cost many thousands of lives, but is haven't disappeared completely in the wake of Assad's fall.
We ask how much of a threat the Islamic State group is today and whether this new power vacuum could present them with a new opportunity for their brand of terror.
So I'm here with Barry Marston, head of the Jihadist media team at the BBC.
Thank you.
Now remind us there was a time back in 2014 in the midst of Syria's civil war, when the Islamic State group was the biggest threat to not only the Assad regime, but also forces allied with the West.
There was real global shock at the way the so called Islamic State group seemed to almost come out of nowhere.
US troops had departed in 2011, almost as if the job had been done.
Jihadist groups weren't going to be a threat again.