These are heady yet baffling times for the world's sole superpower.

Add it up, and the United States, while still the world's largest single economic power, is clearly no longer the sole superpower.

By default, America's position as the world's sole superpower had become unassailable.

We are the sole remaining superpower, and we should be that.

America is not so much the sole remaining superpower as an empire.

But it is also a test of wills between the world's sole superpower and Asia's biggest power.

Still, it is hard to remember a moment when the world's sole superpower seemed less positioned to manage a fractured world.

In short, being a sole superpower isn't what it was cracked up to be 17 years ago.

It increased, he said, with "America's discovery of its role as the sole remaining superpower."

It needs the commitment of major powers, especially the sole superpower.