Gate is a type of Operate. Fly is a type of Operate. Fly is related to Try. 
Terrorism can cause/lead to War. War is related to Side. Rear is a type of Side. 
Gate --IsA--> Operate <--IsA-- Fly <--RelatedTo--> Try 
Terrorism --Causes--> War <--RelatedTo--> Side <--IsA-- Rear 