DAR ES SALAAM, April 19 -- HISTORY, as it turns out, is not merely a collection of dusty events and longdead personalities.

It is, in fact, that one relative who insists on reminding you that you have made this exact mistake before, and worse still, are about to make it again, with enthusiasm. Take the First World War, for instance.

On 28 June 1914 in Sarajevo, Archduke Franz Ferdinand, heir to the AustroHungarian Empire, was assassinated by Gavrilo Princip, a 19-year-old Serbian nationalist.

However, this dramatic assassination was not the root cause of the war, but rather the trigger for a crisis that had been building for years beneath the surface of European politics.

Austria-Hungary reacted swiftly, blaming Serbia and issuing a s...