Staff. Sgt. Michael Risse, 28th Honor Guard Non-Commissioned Officer in charge, and (back) Senior Airman Joshua Edwards, 28th Civil Engineer Squadron heat ventilation and air conditioning craftsman, shake the hands of the three last surviving Navajo code talkers at Mt. Rushmore National Memorial during the 2009 Independence Day celebrations. The code talkers used a special code based on the unwritten Navajo language to transmit messages, making it futile for the Japanese enemy to decipher American battle communications about the time and place of attack. The complex syntax and complicated tonal qualities of the Navajo language baffled even the most experienced linguists. (U.S. Air Force photo/Airman 1st Class Adam Grant)