▁the ▁time ▁his ▁book ▁was ▁available , ▁publications ▁were ▁becoming ▁more ▁restricted ▁and ▁the ▁extent ▁of ▁the ▁Soviet ▁threat ▁of ▁bi ological ▁weapons ▁was ▁being ▁over st ated ▁by ▁Congress ▁and ▁the ▁media . ▁In ▁ 1 9 6 9 , ▁Harvard ▁bi ologist ▁Matthew ▁Mes el son ▁argued ▁that ▁the ▁bi ological ▁war fare ▁programs ▁would ▁eventually ▁hurt ▁US ▁security ▁because ▁potential ▁enemy ▁nations ▁could ▁easily ▁em ulate ▁these ▁weapons . ▁ ▁The ▁general ▁population ▁remained ▁un in formed ▁of ▁any ▁break through s ▁concerning ▁bi ological ▁war fare . ▁This ▁included ▁new ▁production ▁plants ▁for ▁anth ra x , ▁bru cell osis , ▁and ▁anti - c rop ▁agents , ▁as ▁well ▁as ▁the ▁development ▁of ▁the ▁cluster ▁bomb . ▁The ▁U . S . ▁public ▁was ▁also ▁una ware ▁of ▁on going ▁studies , ▁particularly ▁the ▁environmental ▁and ▁open - air ▁experiments ▁that ▁were ▁taking ▁place . ▁One ▁of ▁the ▁more ▁controvers ial ▁experiments ▁was ▁conducted ▁in ▁ 1 9 5 1 , ▁when ▁a ▁dis pro port ion ate ▁number ▁of ▁African ▁Americans ▁were ▁exposed ▁to ▁the ▁fung us ▁As per g ill us ▁f um ig atus , ▁to ▁see ▁if ▁they ▁were ▁more ▁sus cept ible ▁to ▁in fection . ▁Some ▁scient ists ▁reason ed ▁that ▁such ▁knowledge ▁would ▁help ▁them ▁prepare ▁a ▁defense ▁against ▁a ▁more ▁dead ly ▁form ▁of ▁the ▁fung us . ▁The ▁same ▁year , ▁workers ▁at ▁the ▁Nor folk ▁Supp ly ▁Center ▁in ▁Nor folk , ▁Virginia , ▁were ▁un know ingly