Why understanding seems stuck:
I count five kinds of nanotechnology, of which only three are called by that name. Of the three, one is a revolutionary prospect, one is a fantasy, and the third is mostly materials science. As for the other two kinds, one is the heart of today’s greatest technological revolution, while the other is the basis for progress toward the revolutionary prospect — but neither of these is called “nanotechnology”.
This may seem confusing, and it is. Indeed, people who think they know something about “nanotechnology” often have a lot to unlearn, and would be better off knowing basic physics and chemistry and starting from there. This situation makes it extraordinarily difficult to have a productive conversation about what really matters.
Here’s a compact summary in a nice, legible png image:
Please copy or link the above wherever it might surprise someone: