you are likely to find Rifle in/at/on Army. Army is related to Defense. Defense is the opposite of Offense. 
Violent is related to Fight. Fight is related to People. People is related to Civilization. 
Rifle --AtLocation--> Army <--RelatedTo--> Defense <--Antonym--> Offense 
Violent <--RelatedTo--> Fight <--RelatedTo--> People <--RelatedTo--> Civilization 