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Isis has been horrifying the world with its sickening acts of brutality since it seized vast areas of territory in Iraq and Syria and declared a self-styled 'caliphate' last year.
Despite an international military coalition being drawn up against it, experts have warned it could take many years before it is fully dislodged, and its ideals could take even longer to defeat.
Now, Barack Obama has broken new ground in speaking out about Isis's swift rise.
In an interview with Vice News, the US president appeared to directly connect Isis to the 2003 invasion of Iraq by the administration of George Bush:
Isis is a direct outgrowth of al-Qaeda in Iraq that grew out of our invasion. Which is an example of unintended consequences. Which is why we should generally aim before we shoot.
Watch the full Vice News interview below:
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