This article is from the soc.history.what-if FAQ, by Anthony Mayer anthonyemayer@yahoo.co.uk with numerous contributions by others.
No, nor any other people from the Old World who might have discovered
the New. Even apart from a considerable technical edge (guns, but also
metal working, shipbuilding, etc.), the Europeans had a decisive
advantage because of their diseases. Due to their late settlement of
the continents and lack of domesticated animals, the native Americans
lacked any immunity to most Old World diseases, which meant a
catastrophic population collapse (definitely higher than 50%, and
perhaps more than 90%) in the first generations following contact.
Deaths on a similar scale will necessarily follow *any* extensive
contact between the hemispheres.
 
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