It isn’t often that a country – even the sole superpower – turns the world upside down overnight. But in electing a young African-American from an impoverished single-parent background to replace a deeply unpopular plutocrat from an ageing political dynasty, America has pulled off an act that would have left Houdini breathless.

There will be time to pour over the extraordinary demographic shifts that underlay Barack Obama’s landslide victory on Tuesday night – the fact that more than 40 per cent of America’s 18-30 “millennial generation” are non-white, that African-Americans, Hispanics and other minorities turned out in record numbers to bring Mr Obama to victory, and that it is these groups that will increasingly dominate America’s future.