During the height of the Vietnam War, the United States dropped more bombs on neighboring Laos than over Germany and Japan in World War II combined. Thirty percent of those bombs did not explode. ABC News' Bob Woodruff returns to Laos to speak with victims and their families to see how America's "secret war" has impacted their lives.

One of the temples in Vientiane, Laos.
Kaijing Xiao/ABC News