<P> In 1994, Ted Sampley, a POW / MIA activist, determined that the remains of the Vietnam Unknown were likely those of Air Force 1st Lt. Michael Joseph Blassie, who was shot down near An Lộc, Vietnam, in 1972 . Sampley published an article in his newsletter and contacted Blassie's family, who attempted to pursue the case with the Air Force's casualty office without result . In January 1998, CBS News broadcast a report based on Sampley's investigation which brought political pressure to support the identification of the remains . The body was exhumed on May 14, 1998 . Based on mitochondrial DNA testing, Department of Defense scientists confirmed the remains were those of Blassie . The identification was announced on June 30, 1998, and on July 10, Blassie's remains arrived home to his family in St. Louis, Missouri; he was reinterred at Jefferson Barracks National Cemetery on July 11 . </P> <P> The slab over the crypt that once held the remains of the Vietnam Unknown has since been replaced . The original inscription of "Vietnam" and the dates of the conflict has been changed to "Honoring and Keeping Faith with America's Missing Servicemen" as a reminder of the commitment of the Armed Forces to the fullest possible accounting of missing service members . </P> <P> The tomb guards are soldiers of the United States Army . The first military guards were troopers from the 3rd Cavalry, "Brave Rifles", who were posted nearby on Fort Myer . Since April 6, 1948, (known then as "Army Day"), when the regiment was reactivated, it has been guarded by soldiers from 3rd Infantry Regiment, "The Old Guard". The Old Guard is also posted to Fort Myer, Virginia, adjacent to Arlington National Cemetery . It is considered one of the highest honors to serve as a Sentinel at the Tomb of the Unknowns . Fewer than 20 percent of all volunteers are accepted for training and of those only a fraction pass training to become full - fledged Tomb Guards . This attrition rate has made the Tomb of the Unknown Soldier Guard Identification Badge the second least - awarded qualification badge of the United States military (the first being the Astronaut Badge). </P> <P> The soldier "walking the mat" does not wear rank insignia, so as not to outrank the Unknowns, whatever their ranks may have been . Non-commissioned officers (usually the Relief Commander and Assistant Relief Commanders), do wear insignia of their rank when changing the guard only . They have a separate uniform (without rank) that is worn when they actually guard the Unknowns or are "posted ." </P>

Who protects the tomb of the unknown soldier
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