The passage discusses the important role that Navajo code talkers played during World War II. It explains that the U.S. Marine Corps recruited Navajo men to develop a code based on their native language, which was unintelligible to enemy forces and unable to be deciphered. The code talkers helped transmit vital military communications securely on the battlefield. Developing equivalents for technical terms in Navajo was challenging but an alphabet-based system was devised. The code talkers made significant contributions to the U.S. war efforts and their role remained secret for many years after the war.