As Robert Kaplan noted in "Balken Ghosts", all these factions want is a "return to their historical boundaries". The problem is the "historical boundaries" happen to coincide with the greatest expansion of that group's power and influence.
Ralph Peters, although a very astute writer, also misses (or is perhaps not emphasizing) the point that boundaries are not static, but change through time as demographics and even climate change. China's western boundary has changed over the millennia to follow the ebb and flow of arable land. In cold, dry periods, the Steppe expands to the east and the nomads become dominant, Han farmers are forced out and the Imperial government can no longer hold the region. During warmer, wetter periods, the Steppe moves west, the Han farmers can occupy "new" farm land (and the nomads no longer have forage for their herds and horses), and Imperial rule can be asserted over the territories again.
We have difficulty grasping these concepts because in our experience "Nation States" are virtually permanent features on the landscape. (Historians and educated people know this is not true, but even the USSR or Yugoslavia lasted over 70 years, enough to be part of the landscape for several generations). All our institutions revolve around the explicit or implicit existence of Nation States, which is another difficulty when dealing with entities like the Kurds or Pashtun people. NGO's and non state actors like the ISI fall into similar institutional and mental "blind spots". We may have to study the Middle Ages in Europe to understand the new landscape of sub and trans national entities with "state" powers.