Since last Veteran’s Day, Ken Burns’ in-depth documentary on the Vietnam War has aired. It is a powerful reminder of an unpopular war in which many “baby boomers” fought and died. It also prompts memories of the brutal treatment of American POWs and 1,350 who were listed as missing in action after the war ended. Some remain lost today.

Among the 571 American prisoners released in the winter of 1973 was U.S Army Maj. Ed Carlson, whose last assignment was senior Army advisor to the Washington National Guard.

Carlson, a 29-year veteran, was captured near the end of the war. He was held in a jungl...