The revenue comes from foreign donations, drug money, "protection" money and criminal activity like smuggling and kidnapping. And as officials note, the money goes a long way. "The insurgency is a relatively cheap war for the Taliban to fight," an August report out of the Senate Foreign Relations Committee said, noting that money buys "a lot" of rifles, explosives, grenade launchers and foot soldiers known as "$10 Taliban" since that's their day's pay. The Taliban do have a system for incentive pay, as the soldiers get bonuses -- double or triple pay -- for planting improvised explosive devices. And they...