There's also reports that the White House at the time knew Iraq no longer possessed WMD's but had already taken the decision to attack in the near future and all they needed was a reason to do so. They simply made the intelligence fit the policies already in place and away they went. And reading through the Telegraph's article I get the distinct impression anything stored there requires means way beyond the capability of ISIS to weaponize, it's all "potentially" and "possibly". Having deadly chemicals and having WMD's are not the same thing. 

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