
http://www.boardthebard.com/attachments/1578.pdf
The poet uses simple questions and answers to describe what happened to the people and culture of Vietnam during the Vietnam War. The horror of what happened is understated, the person replying to the questions always polite, always addressing the questioner as "Sir", while describing the horrors of the war, "there was time only to scream", in contrast to what had gone before, "when peaceful clouds were reflected in the paddies".
One group of students performed this poem as if the questioner was a torturer/interrogator, and the person replying a victim. That brought out the hidden violence in the poem very well.
You only have to look at the picture here - Vietnamese children running from an airborne attack - to see the truth underlying the matter of fact tone of the poem.