Large parts of the northern hemisphere continue to struggle with the legacies of the great European empires – Habsburg, Russian, and Ottoman – that collapsed in WWI’s wake, or whose decline, like that of the British Empire, was initiated by the war and sealed by its even bloodier sequel a generation later. The resulting fracture zones – in the Balkans and the Middle East, for example – are the source of some of today’s gravest risks to regional and even world peace.