▁ ▁Cont inu ing ▁a ▁rapp ro ch ement ▁begun ▁during ▁the ▁N ixon ▁administration , ▁Carter ▁sought ▁closer ▁relations ▁with ▁the ▁People ' s ▁Republic ▁of ▁China ▁( P RC ). ▁The ▁two ▁countries ▁increasing ly ▁collabor ated ▁against ▁the ▁Soviet ▁Union , ▁and ▁the ▁Carter ▁administration ▁t ac it ly ▁cons ented ▁to ▁the ▁Chinese ▁invasion ▁of ▁Vietnam . ▁In ▁ 1 9 7 9 , ▁Carter ▁extended ▁formal ▁diplom atic ▁recognition ▁to ▁the ▁P RC ▁for ▁the ▁first ▁time . ▁This ▁decision ▁led ▁to ▁a ▁bo om ▁in ▁trade ▁between ▁the ▁United ▁States ▁and ▁the ▁P RC , ▁which ▁was ▁purs uing ▁economic ▁re forms ▁under ▁the ▁leadership ▁of ▁D eng ▁X ia op ing . ▁After ▁the ▁Soviet ▁invasion ▁of ▁Afghan istan , ▁Carter ▁allowed ▁the ▁sale ▁of ▁military ▁supplies ▁to ▁China ▁and ▁began ▁negoti ations ▁to ▁share ▁military ▁intelligence . ▁In ▁January ▁ 1 9 8 0 , ▁Carter ▁un il ater ally ▁rev oked ▁the ▁S ino - American ▁Mut ual ▁Def ense ▁Tre aty ▁with ▁the ▁Republic ▁of ▁China ▁( RO C ), ▁which ▁had ▁lost ▁control ▁of ▁main land ▁China ▁to ▁the ▁P RC ▁in ▁the ▁Chinese ▁Civil ▁War , ▁but ▁retained ▁control ▁the ▁island ▁of ▁Taiwan . ▁Carter ' s ▁ab rog ation ▁of ▁the ▁treat y ▁was ▁challeng ed ▁in ▁court ▁by ▁conserv ative ▁Republic ans , ▁but ▁the ▁Supreme ▁Court ▁ruled ▁that ▁the ▁issue ▁was ▁a ▁non - just ici able ▁political ▁question ▁in ▁Gold water ▁v . ▁Carter ' '. ▁The