?I personally think that using the term Isil or ?so-called? would be better than what [the BBC] currently do,? Cameron said. ?I don?t think we?ll move them all the way to Daesh, so I think saying Isil is probably better than Islamic State because it is neither, in my view, Islamic or a state.?
http://www.bbc.co.uk/news/uk-33195611He's complaining about the use oft the words 'Islamic State' rather than IS, even though IS is short for Islamic State. If fewer in the media had used those words, IS or ISIL might have become something similar to what happened to Al Qaida
If you look at what Bin Laden said when complaining about abridgement of his organizations name
In this letter, Bin Laden regrets that his organizations original name, ''Qa'ida al-Jihad'', has come to be known as simply ''al-Qa'ida.'' The abridgement, he writes, ''reduces the feeling of Muslims that we belong to them, and allows the enemies to claim deceptively that they are not at war with Islam and Muslims.'' Rather, the United States could claim that it was at war only with the al-Qaida organization, which it depicted as ''an outside entity from the teachings of Islam.''Bin Laden complains that Obama has ''repeatedly'' made this argument. Therefore, he concluded, if al-Qaida adopted a new name, which included a reference to Islam, ''it would be difficult for him to say'' that he wasn't at war with Islam.
http://www.slate.com/articles/news_and_politics/politics/2012/05/osama_bin_laden_s_papers_he_wished_obama_would_continue_bush_s_war_on_terror_.htmlIts not only Cameron who is not calling them Islamic State, several western countries are. Last year I read a debate between ISIL and AQ jihadis,and in that debate, AQ jihadis were arguing that Syria is for JN and Iraq for ISIL. To which ISIL jihadis responded that the Islamic state does not recognize Sykes-Picot(which made those countries separate). AQ jihadis pointed out the irony in their name 'Islamic State in Iraq and Syria', as it seems to recognize those borders. A few weeks later ISIS or ISIL became Islamic State and declared a Caliphate.
ISIL relies on Islamic symbols, undermining their message of being the Islamic State or the Caliphate is probably not unreasonable,even though its tricks with words. Maybe those Western countries who don't use 'Islamic State' are being PC. I think they are being more than PC, I think that they read communications between jihadis and the Bin Laden letters before they decided that this is a way to undermine the message of ISIL.