Niall Ferguson is half-right. There has been a geopolitical taper but not of the kind he meant. Instead, there has been a tapering of western geopolitical wisdom.

Has anyone noticed the string of western geopolitical failures over a decade? Despite massive military and financial interventions, Iraq and Afghanistan are failing. Three years ago the US announced: “For the sake of the Syrian people, the time has come for President Assad to step aside.” He remains in office. And now the west is on the verge of handing China a geopolitical gift by alienating Russia.

What explains these failures? It is surprisingly simple. After two centuries of success, the region’s leaders assume their role is to sustain the expansion of western power. Not one of them has wrapped their heads around the new undeniable reality: the real challenge of the west is to manage decline.