The First World?

I’m tired of hearing North America referred to as the first world. This is a new error that has crept into our language of late, and it stems from an ignorance of the original coinage of the term third world. Here’s the story:
In the beginning, there was one known world, comprised of Europe, Asia, and Africa. Then the new world was “discovered” by Columbus, and so the previously known world become the old world, and North and South America become the new world. There was no distinction as to how rich or poor a country was. Technically speaking then, Europe, Africa, and Asia formed the first world, and North and South America formed the second world.
Then sometime in the middle of the previous century, some wit, I'm not sure who because I didn’t feel like doing the research this, but I bet is the author of Future Shock, came up with the term third world to describe those countries that were being left out of the general economic prosperity the world was then experiencing. Third meaning left out, forgotten, overlooked, as in the third wheel on a date. Thus countries previously part of both the first and second worlds became third world nations, a term describing economic circumstances and not locations on a map.I suppose, then, that describing North America now as the first world in reference to our economic status is not entirely unfitting, but it does lead to some confusion as to what exactly is the second world then, and I just thought people should know.