ISIL: What's in a Name

ISIS is in the news, big time.  Captured towns, cities, oil wells and weapons caches.  Mass murders and beheading.  Ethnic cleansing, kidnapping, bank looting.  And in the news, we hear the group responsible for these many acts referred to under different names"  ISIS, IS, ISIL, Al Qaeada rebels.

Then I noticed something that perked my ears up.  President Obama, and his Administration, seem to consistently use the name ISIL, eschewing the use of IS or ISIS, when referring to the band of killers active in Iraq.  The President uses the ISIL variation exclusively in his speeches and public statements.

So, what’s the diff?  All three names are acronyms:  IS = Islamic State;  ISIS = Islamic State of Iraq and Syria; ISIL = Islamic State of Iraq and Levant.  Same group, we all know the folks we're referring to.  Why differentiate?

Words mean things.  The term Levant, which appeared in English usage in 1497, originally meant the East in general or "Mediterranean lands east of Italy”.   It is borrowed from the French levant 'rising',referring to the rising of the sun in the east,or the point where the sun rises.  – Wikipedia.

Geographically, the term refers to the coastline of the eastern end of the Mediterranean. including some or all of the modern day countries of:  Greece, Crete, Cyprus, Turkey, Syria, Jordan, Lebanon, Israel, Egypt, Libya.  That's a big chunk of territory.  Levant is caliphate-scale language. 

Historically, the timing of the inception of the term levant (1497, per Wikipedia) is also significant.  Late 1400s to early 1500s was a high point for the caliphate, the hey-day of Islamic hegemony.  You probably didn't know that, neither did I.  But then, I didn't have the benefit of being raised up under Islamic instruction.

What sort of message is being sent by insistent official use of "ISIL"?