To Obama, the retrenchment of the West was not only inevitable but to be welcomed. In just the last five or six years the world has been fundamentally transformed. Instead of the old accustomed Western-inspired postwar global order, crafted and ensured by the United States and its European and Japanese partners, there is now mostly chaos, from Ukraine to Syria to the South China Sea. Or, rather, there may be emerging new rules, given that we are still frozen in a Wild West moment, when everyone in the saloon has drawn his six-shooter, paused, and is wondering what happened to...