History teaching should incorporate disparate opinions and uncomfortable facts but the temptation with contemporary history is to do the opposite. Parents do not generally want their opinions to be challenged in the schools. The Vietnam War is, for example, still a profoundly upsetting and divisive subject in the United States which teachers have often tried to make anodyne. This makes the whole subject less interesting and less accurate. All the combatants in the Second World War have their own history of the period and these different versions need putting side by side to compare the various interpretations. They often disagree not so much on the facts but on the emphasis they place on the different features, the context and causes of this and other pivotal events. Taught sensitively but comprehensively history can be a confidence measure between previously hostile nations, taught one-sidedly or as propaganda it is a major irritant.