Ramadan!

This is coolbert:

Why didn't I think of this. That end of Ramadan 28 July will mean the ISIL offensive against Baghdad will commence in earnest. The Salafi ISIL in emulation of Mohammad will not begin combat operations until that time as mandated by Islamic teaching. The pause to further ISIL advance in Iraq not solely a consolidation as might have been thought to been the case.

The tip from Legal Insurrection and the "bulletin" from ISW as copied and posted in entirety:

"the Institute for the Study of War issued a terse bulletin this week warning of a looming battle to capture Baghdad by ISIS Islamist fighters."

"ISW has observed a step change in ISIS’s activity in Baghdad and its environs that represents an escalated threat. ISW remains vigilant in light of this change with the expectation that ISIS will attempt a main effort before the end of Ramadan on 28 July 2014. ISW is therefore issuing a warning intelligence update for Baghdad.
Given the increase in kinetic activity within Baghdad city, and specifically the renewal of VBIED [vehicle borne improvised explosive device] attacks, it is important to remain vigilant against the threat of an ISIS offensive in the capital, especially before the end of Ramadan on 28 July. ISIS may have positions inside Baghdad city, and ISIS likely retains extensive freedom of maneuver throughout the Baghdad Belts. The defense of Baghdad must take into consideration the possible operational targets of ISIS, as well as its ability to conduct a range of attacks that include mortars and complex attacks upon fixed sites. The military bases within and surrounding Baghdad must also remain prepared to withstand an attack. ISW assesses that BIAP [Baghdad International Airport] is particularly vulnerable at this time."

NOT necessarily capturing the airport but merely rendering ineffective, take-off and landing not possible. A major target neutralized, that situation for the central Iraqi government made even that much more dire.

coolbert.