I think you're making a bit of a false assumption a la Marxism, Hegelianism or Spiral Dynamics that there is a particular set of "stages" through which societies go to get from point A to point B.
Interestingly, one of the small obscure nations in the Mexico Valley was smelting copper at the time of contact but nobody in the region really saw what they were doing as a big deal or especially useful.
With technology, there are two essential factors: whether you know it and whether your society has decided it is useful. Take the Chinese and gunpowder or Mexicans and the wheel -- just because you discover something doesn't mean you are going to make the best use of it.
And the answer to your question is: actually they did. Europeans had barely started making firearms when they got to the Americas -- and within a few generations, people in the Americas started using them. Just as the alchemical theories that the Europeans used to "invent" the gunpowder were stolen from the Arabs and Chinese (who independently invented gunpowder). Most technology is not independently developed.
Why did the Europeans start using firearms a century or so before other people? Who knows? But most tech, whether used by Europeans, Americans, Africans or Asians has come into being because information and materials have moved across cultures.
Can I ask what the purpose of your question is?