As 1967 turned to 1968, American forces had officially been fighting in Vietnam for years, and many believed the Vietnamese Tet holiday would pass uneventfully, as it had in years past. They were wrong. On January 31, 1968, North Vietnamese and Viet Cong forces launched an offensive across South Vietnam, targeting more than 100 towns and cities.  It was the largest operation from either side until that point in the war. Eighty thousand communist troops hoped to spark a mass uprising...