In this case, it was just mental laziness. Yes, even John von Neumann can be guilty of this. E=mc^2 implies a freaking huge ratio in your favor. That makes nuclear energy seem of "virtually limitless" abundance for the same reason that nuclear bombs seem like "virtually unstoppable" weapons. Yet, simple ball bearings or a complex mechanism like an Orion rocket pusher plate can survive close proximity to a nuclear explosion with some judicious engineering. If John von Neumann started looking closely at nuclear energy in the broader context of our industrial and political infrastructure, he might have come to a different conclusion.

My conclusion is this: One of the best places for opportunities to hide is in the mistaken popular applications of basic principles and physical laws. This isn't to say that those principles and laws are incorrect, just that the way most people apply them either doesn't go far enough, or fails to also include an economic analysis.

This tells us how to look for opportunities hiding behind other common misapplications of principles. (Not necessarily ones involved in nuclear energy.)