There are several ways in which we could justify this statement, but also many ways in which we would be able to challenge it.
In terms of support, we can argue that this was the case because the cultures of America did not have any significant contact with the cultures of Africa or Oceania until the arrival of the Europeans. We can also support this by the fact that the Andean cultures and the Mesoamerican cultures had no contact with each other.
However, there are several factors that show that this was not the case, or that the claim might be exaggerated. For example, we know that many groups in Africa had extensive interactions with each other. For example, the expansion of the Bantu that took place over large regions in Africa. Another challenge could be the extensive contact that many Mesoamerican groups had with each other.
Saudi Arabia and Yemen border the Red Sea on the east while Sudan, Eritrea, Djibouti and Egypt border it on the west. Egypt also borders the Red Sea on the north along with Israel and Jordan. Hope this helps. Have a nice day.
Don't fight protracted insurgencies in distant countries, when you understand little of the language or culture, and there is a nationalist tendency in the population. Don't spend massive resources in countries with an imperial history that will only resent your presence in the long run, and that are very difficult to change, or perhaps not interested in democracy at all.
