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With nuclear technology entering its seventh decade of use, one may have surmised that issues surrounding the safety of this technology would be well agreed upon with a consensus view of the potential pitfalls involved in nuclear security. However, as Scott Sagan reveals in his book called The Limits of Safety, the problems surrounding atomic safety lie not in the components of the system, but in the paradigm that structures our view of atomic safety. By highlighting near misses from the Cuban Missile Crisis and other events, Sagan uncovers how close the world may have come to accidental detonations and possible accidental nuclear war. Sagan interprets these events from two different perspectives concerning organizational learning: the high reliability organization learning theory (an optimistic view of nuclear safety) and the normal accident theory (more pessimistic). These perspectives present and interpret the near misses in totally different lights, as this analysis of the competing paradigms of nuclear safety is the essence of his work. Based on his research, Sagan was forced to change his prior view of nuclear safety and concludes with recommendations to make nuclear weapon systems more secure.
High reliability theory holds that accidents can be prevented through good organizational design, that safety is the priority organizational objective (development of a "high reliability culture"), that redundancy enhances safety, and that trial-and-error learning from near misses can be effective (implying use of sophisticated forms of trial-and-error organizational theory). Essentially, this model argues that accidents can be avoided given the proper set of precautions and organizational learning. Given that there have never been any (known) unauthorized detonations of nuclear weapons, one may conclude that the high reliability model accurately describes the realities of nuclear safety thus far. However, the weaknesses in such a perspective concerning nuclear safety do not become evident until examining normal accidents theory.
Greatly influenced by Charles Perrow's book called Normal Accidents and by integrating these ideas with the garbage can theory of organizational behavior creates Sagan's normal accident model of organizations. This view holds that accidents are inevitable in complex and tightly coupled systems, that safety is only one of a number of competing objectives, that redundancy increases the complexity and opaqueness of the system and thereby may compromise safety (indeed the provocative view that redundancy may even cause accidents) and that political infighting is a serious barrier to organizational learning. This model perceives organizations as rational actors capable of mistakes, and it emphasizes the structural and political nature of nuclear safety.
The weaknesses of high reliability theory then become more evident once the alternative is presented. First, inconsistent goals and conflicting interests are inherent in organizations, and this can increase the probability of accidents. Second, redundancies in features of nuclear safety can actually increase risks. This is due to systems that are not independent of each other interacting in unexpected ways. Also, the overlap in systems caused by redundancy makes mistakes less visible. Thus, organizations are unlikely to adjust for mistakes that they do not perceive exist. Third, some accidents cannot be anticipated. Hence, effective contingency plans may not exist. Lastly, the politics of nuclear safety places restrictions on organizational learning. As Sagan asserts, blame for accidents is often misplaced at low levels in the organization (operator error, for example) instead of addressing problems inherent in the system of nuclear oversight. Sagan is also quick to point out that high reliability theory implies a full disclosure of high-risk (or near miss) nuclear incidents that does not exist. He indicates that much of the information he obtained via the Freedom of Information Act is only a partial account of nuclear accidents in the U.S. military.
After having laid out the propositions and assumptions of these competing theories, the books addresses the basic question of which of the two theories is more accurate drawing from analysis of the Cuban missile crisis, the B-52 Thule bomber crash, the performance of US missile warning systems (specifically in false alarms in 1979 and 1980), and others. This selection of case studies is a tough test for normal accident theory. One would expect that the all-pervasive and dreadful consequences of an accidental nuclear war would make nuclear weapons safety a first priority at all levels of all involved organizations. The reader is left un-reassured of this. Scott Sagan provides numerous examples of political infighting, of organized cover-up, of normalization of errors, of reinterpretation of failure as success, and of conflicts over parochial interests that are serious barriers to organization learning. This is unsettling reading, not the least because Sagan's account is limited to U.S. experience only; the Kremlin does not permit access to its records on nuclear safety.
The research presented by Sagan has major implications for the effectiveness of the theory of deterrence to prevent (accidental) nuclear war. To quote the author, "In light of evidence presented here, the belief that nuclear deterrence can prevent nuclear war under all circumstances should be seen as exactly that: a belief, not a fact" (262). Sagan then listed reasons to doubt the effectiveness of intended deterrence. First, even at the height of the Cold War, the US and USSR did not easily control their nuclear forces. Thus problems in command-and-control operations still exist today. Second, given that the superpowers were unable to structure their nuclear systems in such a way to make accidents impossible, states that will develop nuclear weapons in the future are sure to be less stable than the US and USSR were in their nuclear infancy, thus making nuclear accidents more likely. Third, emerging nuclear powers are under pressing security threats and may perceive the need to keep their nuclear arsenals on high state of readiness. Although the book was written before 1998, the emergence of India and Pakistan as nuclear powers represents these threats to intended nuclear deterrence.