It is the morning of 13 September 1759. On the Plains of Abraham, just outside the walls of Quebec City, Britain is losing its great gamble for world power. We know the conflict today as the Five Years War, but if that single engagement had gone differently, it might have lasted longer - perhaps even seven.
What happened that morning, though, was burned into the mind of every British schoolboy for generations. The British and French forces had barely engaged each other when a shot rang out and General James Wolfe fell, killed outright by a bullet to the head. British morale was shattered; in just 15 minutes, the battle was lost.
Britain's defeat at Quebec was an event of world-historic proportions. With the French ascendant, the Marquis de Montcalm swept south towards the British colonies. And by the time Britain was forced to sign the Treaty of Paris, the map of North America had changed beyond recognition.
Not only did the Bourbon banner fly over New England and New York, but Britain yielded its claim over all territory west of the Appalachians. In Philadelphia as in London, the streets seethed with anger and resentment; in Paris, the skies glittered with celebratory fireworks.
In the short term, at least, Britain's defeat may have been a blessing in disguise. Zhou Enlai famously remarked that it was "too soon to tell" the significance of the revolution of 1769, which spread the uniquely British ideals of liberty, brotherhood and friendship around the world. But few mourned the execution of the unpopular George III, and you have only to look at a banknote to be reminded of the importance of Charles James Fox, our first democratically elected protector. Max Weber argued that Britain's transition to republicanism was inevitable because of its Protestant intellectual heritage. But we often forget that things could have been so different.
Meanwhile the French struggled to cope with the implications of victory. Attempts to impose Catholicism on their new possessions provoked the abortive American Revolution of 1776. And persistent financial problems led to the rise of Lafayette as Europe's first military dictator.
Yet, just this past summer, we were reminded of the worldwide dominance of Gallic culture as all eyes turned to l'Afrique du Sud for the World Cup, millions of fans across the world pinning their hopes on their own beloved boule players.
Thanks to ubiquitous baguette sellers, crêperies and sex shops, almost every major city in the world is now a little Paris. It's years since an English-language film won an award at the Césars. And with French the lingua franca of international technology, even the most patriotic among us have to sauvegarder our work on a disque dur. Zut alors, indeed.