The Fertile Crescent in the Middle East was the geographically lucky origin of not only wheat and barley (VERY important staple crops) but also of most of the domesticated animals. This herding and farming culture provided enough agricultural excess to support non-herders and non-farmers, who were able to develop technology and skills (like writing). Their closeness to animals also exposed these people to germs, which over hundreds of years they developed a genetic immunity to. The ideas, animals, and crops easily spread along an East-West axis (where people were attracted to similar climates and lengths of days) into Europe, Asia, and Northern Africa. So in the end, Europeans had guns, germs, and steel on their side.
The Americas, unlike Eurasia, are narrowly shaped along the East-West axis and broadly shaped along the North-South axis. Therefore, although there were some crops, one domesticated animal (the llama), and one written language (that of the Mayans in Central America), technology and food was not easily interchanged in the Americas. When Europeans came with their guns, germs, and steel, the native population was decimated.
Although I find this idea very fascinating and fairly convincing, I have a few qualms. First of all, I understand that the area around Panama is very narrowly shaped along the East-West axis, making exchange of ideas and goods difficult. However, North America, at least, is not too VERY long and narrow. Not narrow enough for this to be the main factor which slowed the progress of civilization. The documentary also does not address the reason why the Europeans apparently won this war. After all, if it is merely geographical closeness along an East-West axis to the Fertile Crescent, then wouldn’t Asia be just as likely to succeed as Europe? And, in fact, the moors were quite successful for quite a long while. So why didn’t they colonize the Americas, India, Africa, and Australia?
My answer to that is “just wait.” The war isn’t over yet.