Was there a specific person, nation or behavior responsible for starting the Great War (WW1?) Whether you think blame can be laid to rest at the foot of one entity or there is enough blame to go around to all of the participants, you need to include specific detailed evidence to support your claim. Explain why you attribute blame to your choice. Then...explain what we can learn from this. For example, if you blame the secret alliances for the start of the war, you should explain why and how (as in specific steps—perhaps a public registry on alliances) that reason can be prevented in the future. Or if you blame the terrorist organization behind the initial assassination that sparked the war, you should explain why and how (as in specific steps—perhaps government responsibility for terrorist actions against visiting dignitaries) that reason can be prevented in the future. Remember, you and your classmates will have different opinions as to whom responsibility for World War I should rest—so keep an open mind and be analytical (rather than emotional) in your comments.

Purpose—when we understand the causes of past events, we are then better prepared to prevent them should they rise again—at least, that's the theory!