Some thoughts on the scenrio should the US grasp the inevitable thorn.
A US disengagement would result in the partition of the country into regions like “Somalia” and “Somaliland.” The Pashtun heartland resembling the former, and the central, northern and western regions the latter. Pakistan would regain strategic depth by creating a “Grand Waziristan,” comprising of Pashtun-dominated border regions of Pakistan and Afghanistan. Russia would gain in further influence over Central Asian states. The Pashtun heartland would likely revert to an Islamist, Sunni, Pashtun caliphate. Trump might try to negotiate some kind of deal with Russia to facilitate as face-saving a US withdrawal as possible. It would amount to an even bigger defeat with more loss of face than the Vietnam debacle. Trump's justification will be 'the money'.