Jared Diamond wrote a fascinating book that purports to explain, in a very broad way, the development of civilization. It has several explanations for the development of Eurasian civilization rather than American civilization.
Domesticated Animals: In Eurasia, there were several large domesticated animals, including the cow and horse. This had advantage for animal-powered farming and transportation, as well as infecting the Eurasians with numerous diseases the Americans had no resistance to. Diamond places great importance on diseases in human development, and likens the results of making contact with a more diseased civilization to being digested.
Direction of Expansion It's easier for a civilization to expand in a roughly east-west direction than a north-south direction, since climate is more similar east-to-west (an example would be the lack of horses in South Africa until imported by sea, since they couldn't go by land through the tse-tse fly zone). Eurasia extends more east-west, and America more north-south, as does Africa.
Food Production Wheat is a better grain than corn, in terms of nutrition supplied per unit effort.
There are other factors, but it's at least a well-written book, and superficially plausible.
How accurate, well-supported, and well-regarded is this book?