One is FORCED to focus on the activities of 'IS' since they are unlike any 'RF' (Retaliatory Force') which may have preceded them and it is very difficult to imagine how the 'Problem' they pose may be resolved.
'Saddam Hussein' described America as 'The Great Satan' when they embarked on their unlawful campaign of destruction ('Shock and Awe') and rained death and destruction (Aerial Bombardment) upon the relatively defenceless sleeping civilians of Baghdad, relatively defenceless because they did not possess the weaponry to counter the 'High Altitude Bombardment' which heralded the onset of the murderous slaughter which was 'Shock and Awe' and was condemned later as an action based upon a tissue of lies.
'Baghdad', the birthplace of 'IS' and the determination of those that rose up (Retaliatory Force) to vent their rage upon 'Western Aggression' (colour it which way you will) which now, on hindsight, is so obvious.
Substitute the term 'Great Satan' for 'Shatan' (the Devil) and the scene is set for a battle twixt the forces of 'Evil' and those who oppose it, 'IS'.
Since 'IS' consider themselves to be 'Dead' already (confirmed on many occasions) they obviously do not fear death, neither will they countenance defeat since (in THEIR perspective) they cannot be defeated.
Since the 'Devil' is associated with the most atrocious acts imaginable, 'IS' is bound to emulate 'Devilish ' responses (as THEY see it) and commit to the atrocities WE have witnessed so regularly since it all began.
With such a formula, it is inconceivable that the 'RF' of 'IS' can be defeated by force of arms and, sooner or later they must be negotiated with (hopefully sooner) and certain of their demands met.
What those demands may be, WE are not privy to BUT, utter defeat is out of the question and the West does not really have a clue about how they can clear up the mess they have created.
Be sure of one thing, negotiations are under way 'At a Pace' and 'I' believe that the main obstacle to peace is, how to extricate oneself (the West) with some degree of credibility.
Perhaps the good old 'Yankee Dollar' (by container-load) might come to the rescue.... I doubt it.