The evolution of American strategic doctrine since the early 1970s is said to have been a transition away from deterrence, towards a so-called "warfighting" doctrine. Discussion of this transition was initiated by the "Schlesinger Doctrine" and National Security Decision Memorandum (NSDM) 242 in 1974, 1 and continued under each successive administration: best illustrated by Presidential Directive (PD) 59 during the Carter Administration, 2 and National Security Decision Directive (NSDD) 13 under the Reagan Administration. 3 US doctrine during this transition has emphasized the capability for limited strategic options, countermilitary and counterpolitical control targeting, postattack continuity of government, and the potential for waging a prolonged nuclear conflict, inter alia. In effect, this so-called 167"warfighting" transition has focused primarily upon revising US nuclear targeting policy, and emphasizing "counterforce" targeting even more than had been the case previously.