Code-talker paradox
The code-talker paradox is an issue in linguistics that brings into question some fundamental ideas of the nature of languages. Basically, how can a language both enable communication and block communication?
This term, coined by Mark Baker raises the issue of how Philip Johnston and the code talkers were able to communicate in a way such that human beings created references that were mutually intelligible to each other but completely unintelligible to everyone who was not familiar with the structure and meaning of the signals.
Native American languages were used militarily by the US during World War I and in World War II. Hitler was aware of the World War I efforts and even mounted an anthropological project to learn some of those languages during the 1930s. The best known were the Navajo Code-Talkers used by the US Marines in the Pacific Theater against Japan. The plot of the movie Windtalkers centers around this.