Archduke Franz Ferdinand in Serbia, which triggered a series of events that led, rapidly but seemingly unintentionally, to World War I. This got me thinking about how this seemingly minor event compares to other important events in world history, and how history might have been different had that assassination attempt failed.

- In response to the assassination, Austria-Hungary declared war on Serbia, Russia then mobilized in defense of Serbia, Germany jumped in to help Austria-Hungary, France and Britain responded by coming to Russia's defense, and so on.

- World War I profoundly affected Europe and the modern world -- among other things, it completely re-defined the borders of central and Eastern Europe and led directly to the Russian Revolution and to the establishment of Communism there, and therefore as a serious force globally.

- The war and its aftermath also led directly to the rise of Hitler and the Nazi party in Germany, and therefore to World War II. The terrible carnage and resulting war fatigue was probably a major factor in the feeble response of the Western democracies to Hitler in the 1930s.

So, had the assassination attempt failed, possibly the world could have avoided the two bloodiest wars in history, Hitler, Naziism, the Holocaust, the creation of the Soviet Union, the rise of Communism globally, the Korean & Vietnam wars, Mao, and so on; even jokes about cheese-eating surrender monkeys (in fairness, not because of WWI, in which the French fought heroically). Even the Middle East might look very different today, as the early history of Israel was so strongly influenced by the Holocaust and naziism.

Maybe I'm overstating it, but it's hard to exaggerate the impact of this one event. Certainly the world might be a very different place had it not happened. How many other single events in world history have had such a profound impact on world history?