▁served ▁for ▁eight ▁years ▁as ▁an ▁under cover ▁case ▁officer ▁for ▁the ▁C IA , ▁first ▁in ▁southern ▁Afghan istan ▁and ▁later ▁in ▁the ▁Middle ▁East , ▁particularly ▁Sy ria . ▁The ▁book ▁was ▁heavily ▁red act ed ▁by ▁the ▁C IA ▁prior ▁to ▁publication . ▁ ▁The ▁phrase ▁" left ▁of ▁bo om " ▁is ▁a ▁military ▁id iom ▁that ▁refers ▁the ▁U . S . ▁military ' s ▁effort ▁to ▁dis rupt ▁ins urg ent ▁cells ▁before ▁they ▁can ▁build ▁and ▁plant ▁bomb s . ▁ ▁Over view ▁Left ▁of ▁Bo om ▁describes ▁L aux ' s ▁time ▁as ▁a ▁case ▁officer ▁in ▁Afghan istan , ▁which ▁included ▁a ▁tour ▁in ▁Afghan istan ▁during ▁the ▁Afghan ▁sur ge ▁and ▁another ▁to ▁K and ah ar ▁during ▁the ▁operation ▁that ▁killed ▁Os ama ▁bin ▁L aden . ▁As ▁an ▁under cover ▁case ▁officer , ▁L aux ▁was ▁trained ▁in ▁Pas ht o ▁prior ▁to ▁his ▁deployment ▁along ▁the ▁Afghan istan - P ak istan ▁border , ▁however , ▁L aux ▁writes ▁the ▁dialect ▁of ▁Pas ht o ▁he ▁learned ▁was ▁not ▁spoken ▁in ▁the ▁region , ▁thus ▁making ▁communication ▁with ▁local ▁assets ▁initially ▁difficult . ▁The ▁role ▁that ▁Pakistan ' s ▁Director ate ▁for ▁Inter - Services ▁Int elligence ▁played ▁during ▁this ▁time ▁is ▁all ud ed ▁to , ▁but ▁Pakistan ▁is ▁never ▁specifically ▁mentioned ▁in ▁the ▁book . ▁ ▁L aux ▁writes ▁about ▁his ▁time ▁in ▁Sy ria ▁meeting ▁with ▁leaders ▁of ▁the ▁Sy rian ▁re bell ion ▁in ▁ 2