Was Three Mile Island the main driver of US nuclear power's decline?

The short answer:  no.

The Bulletin of the Atomic Scientists just published a feature article by Nate Hultman and me that addresses this very question.  All the articles in that issue are available for free during the month of May 2013–after that they go behind a paywall.

Here’s the abstract of the article, to whet your appetite:

It is tempting to attribute variations in support for nuclear power to prominent accidents such as Three Mile Island in the United States or Fukushima in Japan. To illuminate how such attribution can be problematic, the authors discuss the historical context of the Three Mile Island accident in the United States. They point out that the US nuclear industry faced major challenges even before the 1979 accident: Forty percent of all US reactor cancellations between 1960 and 2010, they write, occurred before the accident in Pennsylvania. While safety concerns were undoubtedly a driver of public aversion to new nuclear construction in the United States, the nuclear industry already faced substantial economic and competitiveness obstacles, much like the nuclear industry worldwide before Fukushima.

This was a complete update and rewrite of a much longer post Nate and I did for Koomey.com that was reposted on Climate Progress.

The full reference is Hultman, Nathan E., and Jonathan G. Koomey. 2013. “Three Mile Island:  The Driver of US Nuclear Power’s Decline?"  Bulletin of the Atomic Scientists.  vol. 69, no. 3. May/June. pp. 63-70.[http://bos.sagepub.com/content/69/3/63.abstract]

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