Psychotropic drugs have been used for the purpose of suppressing fear and enabling murderous rage for a long time. In Dispatches, his extraordinary book about the war in Vietnam, Michael Herr passes this along about the use of drugs by American soldiers: Going out at night the medics gave you pills. . . . I knew one 4th Division Lurp [Long-Range Reconnaissance Patrol] who took his pills by the fistful, downs from the left pocket of his tiger suit and ups from the right, one to cut the trail, the other to send him down it. He told me that...