Thirty years ago the last American troops left Vietnam. More than 58,000 Americans died in that unpopular war, and hundreds of thousands were wounded or injured. Thousands more carry invisible scars from intense and prolonged combat. Returning soldiers faced an indifferent or hostile citizenry. Frustrated at the slaughter and cost of the war, the protesters vented their anger on the brave soldiers who had endured a year in hell. The protesters cursed at Vietnam veterans, and spat upon them and called them baby killers. I commanded an infantry company during my second tour in Vietnam. Fighting in the jungles and...