A lengthy article by Professor Theo Farrell, ex-Kings War Studies, partly based on his first-hand research with ISAF and the Taliban. IT appears on WoTR from an affiliated website.

He opens with:
Insurgencies are famously difficult to defeat, yet the Afghan Taliban have proven especially so. Accounts of Taliban resilience have focused on both the deficiencies of Western efforts and the Afghan state and on Pakistani support for the Taliban. These accounts fail, however, to reveal the full picture of how the Taliban have been able to survive. Drawing on original field research, this article explores how the Taliban’s success has been shaped by factors internal to the insurgency, namely, the social resources that sustain it and the group’s ability to adapt militarily.

(He ends with) In the end, ramping up the U.S. military effort in Afghanistan risks reenergizing the Taliban’s sense of purpose and uniting a movement that may be beginning to unravel. If the United States is not careful, it could end up bombing its way to defeat in Afghanistan.
Link:https://tnsr.org/2018/05/unbeatable-...fghan-taliban/