title: The enemy system.
mesh_terms: D001290:Attitude; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D005006:Ethnicity / Q000523:psychology*; D006126:Group Processes; D006801:Humans; D009689:Nuclear Warfare; D010819:Physician's Role; D011639:Public Opinion; D011640:Public Policy; D012380:Role