You have to wonder how much of that transaction is saving face? The warlord doesn't have to deal with the messy business of trying to shoot down jets belonging to a well-funded army; the military doesn't have to deal with the difficult business of engaging a warlord with local connections and support. Both sides get to wink and imply that they each got the better end of a "business deal". It's Clausewitz in reverse -- commerce as a de-escalation of war by other means.