That was quite literally what happened, across most of Europe. Franz Ferdinand is shot on the 28th of June, and it's front-page news in Western Europe for maybe a day. Nobody seriously thinks that this could start a continent-wide war. For about four weeks, while a perfect storm of wrong assumptions and misunderstandings between diplomats and ministers gradually builds up to Russia's call for mobilisation on the 31st of July, France is busy talking about a completely different assassination, that of the newspaper editor Gaston Calmette by Henriette Caillaux, a socialite and wife of a former prime minister, who thought Calmette was going to publish intimate letters of theirs that were written while they were both married to other people.

France going from talking about that to hearing declarations of war and mobilising to meet the invading Germans happens in days, its complete whiplash for everyone in France. Imagine if in 1995 the US just abruptly went to war with Russia or something while in the middle of the OJ Simpson trial. Or put this another way; not many people in America were worrying about terrorist attacks or Islamic fundamentalism on the 10th of September of 2001.