In the first two of these cases it was thought of as a one off advancement (eg, see the mythology around the discovery of iron - typically it involves a gift from a god).

In the case of the opium wars, the "lesson" learnt was the same lesson as during the subjection of India and other European colonies, ie: the cultural superiority of the white man.

Obviously is retrospect this was the wrong lesson, but that's what people thought at the time.