[fennecfoxen]

I'd like to think that we have a certain level of understanding of topics like the conservation of energy. We understand that it is possible in theory to liberate enormous amounts of energy from the rest-mass of ordinary matter. However, we also understand that, in general, matter is stable, and this liberation takes place either very slowly, or under extremely energetic conditions. We also understand that building microscopic structures capable of resisting extreme conditions is an extraordinarily difficult engineering problem. Nanostructures that could bring these conditions about? Even more so.

Our level of understanding seems, broadly, a better level of understanding than a 16th century layperson would have of topics like the existence of electromagnetic waves and electricity, let alone the batteries, semiconductors, and software applications of semiconductors which ties them together.