The author seems to be saying that Pastun culture has a historic inclination to resist outside interference from those attempting to impose anything on the Pastuns. I assume he includes sharia and the taliban in those interfering forces.
Sharia has become incorporated into the Pashtun way, although modified enough that Mo probably wouldn’t recognize some aspects.
The author kinds of beats the bush to death, but what I think he’s trying to say is that we need to try to boost those aspects of Pashtun culture that conflict with the Taliban. We’re not going to swing the Pashtun to our side by promoting western values, we may be able to by promoting anti-Taliban Pashtun values.
After all, the Pashtuns have been living there for thousands of years without bothering the USA one bit. They gave the Brits a great deal of trouble, but that’s another story.