As with any writing assignment, you need to plan your answer. For compare and contrast, it is the easiest to make a T chart. On one side, list how the post war voices (this would be what is said about the war during this time period from those who felt the need to discuss it but weren't necessarily there.) So, list how some people shared the same about opinion and what they said that they could agree on. On the other side, list what people were arguing about...what was it about the war that they said to each other where their opinions differed. Then set the essay up with an introduction that includes background information, a personal tie-in, a tie-in with the audience, and end with a thesis statement. The first body paragraph should be the comparisons, the second body paragraph should be about the contrasts, and end the essay with the conclusion.
