The US Government's Afghan policy follows a clear pattern: identify who you dislike most and arm their enemy, then rotate and repeat. During the Russian occupation, arm the mujahideen, even if some of them have some funny ideas. Then arm the Northern Alliance to help take on the Taliban.
That worked fine for getting the Talibs out of power, but now they're an insurgency, best pay them to let you get the weapons through to fight them. Who else can you rely on?
That story also features a security/mercenary company called Four Horsemen International, which is brass neck on an almost admirable scale.
Finally, if paying insurgents not to fight you so they can buy bigger guns doesn't work, and who knows, it might not, you're going to need some new militias, also known as "pockets of tribal resistance". How long before American foreign policy-makers are swallowing a cat to go after this latest crowd?