Kip has previously discussed some of the challenges of the Korengal Valley, and a good overview of the work by CDR Legree, well-regarded commander of the Asadabad PRT in Kunar Province, can be read here.
Interestingly, the Korengal is a magnet for the best and brightest lieutenant colonels in the US Army. The current battalion commander of that area of northern Kunar and southern Nuristan is LTC William Ostlund, part of the US Military Academy Social Sciences mafia (which includes LTC John Nagl) that has been at the forefront of evolving COIN thinking in the US Army. The previous battalion commander in that area, LTC Chris Cavoli, is a Princeton graduate, fluent Russian speaker, and currently responsible for developing COIN training at the Marshall Center in Europe.
If the Afghan government is to extend its influence into incredibly complex Nuristan, then the Korengal is a dangerous reminder of the unparalleled human complexity of Afghanistan's far East and just how little we know about what is out there.
In Nuristan and northern Kunar, a large and varied number of ethnic groups live in separate valleys. Different languages and variations in dialect can make it virtually impossible to find an interpreter in some places.
Extremist Islam has infiltrated some of the valleys of Nuristan and has done so in various religious revivals dating to the time of mass forced conversion during Abdur Rakhman.
(An interesting side note is that the pagan king of Nuristan was not forced to convert, and his steadfastness remains much admired by many Nuristanis. His grandson is the current governor of the province.)
In others, pagan practices such as orgies and wine making periodically re-emerge.
A number of the "Afghan Arabs" settled and married in the area after the anti-Soviet jihad and have become vital for supporting various insurgencies in the east. Here, there is much more raw Wahhabi fundamentalism, but the insurgency is less unified.
Specific grievances by one tribe or another against the central or provincial government result in rebellion, as they have for centuries. In the case of the Korengalis, for instance, lumber is a main source of unrest as well as ethnic and linguistic differences between them and the Pashtun-dominated Peysch River Valley where the seat of government is located.