Bob Kalsu (April 13, 1945 - July 21, 1970) was an All-America tackle at the University of Oklahoma and an eighth-round draft pick by the Buffalo Bills of the American Football League in 1968. Kalsu was a starting guard in 1968. He played the entire season and was the Bills' team rookie-of-the-year. Following the 1968 season, to satisfy his ROTC obligation, he entered the Army as a First Lieutenant (see discussion) and arrived in Vietnam in November 1969. He was killed in action on July 21, 1970 at Ripcord Base near the A Shau Valley.
Lieutenant Kalsu had one child, a daughter. At home in Oklahoma City, his wife gave birth to his son, James Robert Kalsu Jr., on July 23. Mrs. Kalsu was informed of her husband's death only hours later. Kalsu was the only recently active professional American football player to lose his life in the Vietnam War. Retired Cleveland Browns player Don Steinbrunner also died in combat in Vietnam.