North Korea developed its nuclear weapons despite U.S. threats and sanctions largely because it perceived Washington’s hostility as something that depended on the nature of the U.S. rather than on something Pyongyang itself did. 

According to a study that will be published by the Asian International Studies Review, the problem was in an American strategy that was based on an incorrect theory of deterrence. U.S. governments have assumed that deterrence would be most successful if the government insisted on tough measures even when North Korea cooperated: Only a bloody nose could persuade Pyongyang