ISIS calls it Islamic state I think  , in any case this is the same BBC that calls Persian Gulf, gulf with no name so why the surprise? 

Cameron must be counting on the mozlem vote there as this entity truly is islamist state: they practice the "teachings" of the book of violence (aka ghoraan) word by word - granted this book is one of many, but hey....

You can't deny this no matter how you try! It's written there.