What Are Acceptable Nuclear Risks?

When I read Eric Schlosser’s acclaimed 2013 bookCommand and Control: Nuclear Weapons, the Damascus Accident, and the Illusion of Safety, I found a tantalizing revelation on pages 170-171, when it asked, “What was the ‘acceptable’ probability of an accidental nuclear explosion?” and then proceeded to describe a 1957 Sandia Report, “Acceptable Premature Probabilities for Nuclear Weapons,” which dealt with that question.

Unable to find the report online, I contacted Schlosser, who was kind enough to share it with me. (We owe him a debt of gratitude for obtaining it through a laborious Freedom of Information Act request.) The full reportSchlosser’s FOIA request, and my analysis of the report are now freely accessible on my Stanford web site. (The 1955 Army report, “Acceptable Military Risks from Accidental Detonation of Atomic Weapons,” on which this 1957 Sandia report builds, appears not to be available. If anyone knows of an existing copy, please post a comment.)

Using the same criterion as this report*, which, of course, is open to question, my analysis shows that nuclear terrorism would have to have a risk of at most 0.5% per year to be considered “acceptable.” In contrast, existing estimates are roughly 20 times higher.**

My analysis also shows, that using the report’s criterion*, the risk of a full-scale nuclear war would have to be on the order of 0.0005% per year, corresponding to a “time horizon” of 200,000 years. In contrast, my preliminary risk analysis of nuclear deterrence indicates that risk to be at least a factor 100 and possibly a factor of 1,000 times higher. Similarly, when I ask people how long they think we can go before nuclear deterrence fails and we destroy ourselves (assuming nothing changes, which hopefully it will), almost all people see 10 years as too short and 1,000 years as too long, leaving 100 years as the only “order of magnitude” estimate left, an estimate which is 2,000 times riskier than the report’s criterion would allow.

In short, the risks of catastrophes involving nuclear weapons currently appear to be far above any acceptable level. Isn’t it time we started paying more attention to those risks, and taking steps to reduce them?

* The report required that the expected number of deaths due to an accidental nuclear detonation should be no greater than the number of American deaths each year due to natural disasters, such as hurricanes, floods, and earthquakes.

** In the Nuclear Tipping Point video documentary Henry Kissinger says, “if nothing fundamental changes, then I would expect the use of nuclear weapons in some 10 year period is very possible” – equivalent to a risk of approximately 10% per year. Similarly, noted national security expert Dr. Richard Garwin testified to Congress that he estimate the risk to be in the range of 10-20 percent per year. A survey of national security expertsby Senator Richard Lugar was also in the 10% per year range.


FAS Roundup- November 21, 2011

FAS Roundup: November 21, 2011

Interview with former Iranian nuclear negotiator Amb. Hossein Mousavian, petition to assess nuclear threat, stalled declassification of historical satellite imagery, status of China’s nuclear forces, and more.

From the Blogs

  • Declassification of Intelligence Satellite Imagery Stalled: The eagerly awaited declassification of vast amounts of historical intelligence satellite imagery that was supposed to occur this year did not take place, and it is unknown when or if it might go forward. Earlier this year, government officials had all but promised that the declassification and release of miles of satellite imagery film was imminent. But it didn’t happen. Why not?
  • Pre-Publication Review as a Secrecy Battleground: Steven Aftergood writes that the Obama Administration’s uncompromising approach to punishing “leaks” of classified information has been widely noted. But its handling of pre-publication review disputes with former intelligence agency employees who seek to publish their work has been no less combative.
  • A New Intelligence Org on Climate Change is Needed, DSB Says: According to a new report from the Defense Science Board (DSB), the U.S. intelligence community needs an organization that can assess the impacts of climate change on U.S. national security interests in an open and collaborative manner. The CIA already has a Center on Climate Change and National Security. So why would the Intelligence Community need an entirely new organization to address the exact same set of issues?
  • CIA Sees “Little Likelihood” of Finding Docs on Secrecy Reform: The Fundamental Classification Guidance Review (FCGR) was ordered by President Obama in his December 2009 executive order 13526 (section 1.9) as a systematic effort to eliminate obsolete or unnecessary classification requirements.  It is the Obama administration’s primary response to the problem of over-classification, and it has already achieved some limited results at the Department of Defense and elsewhere. That being said, it can’t possibly work if agencies don’t implement it. And so far there is no sign of the mandatory implementation at CIA.

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