The man in the Oval Office, argues Toby Harnden, may already be preparing for a role as a post-president in a post-American world.

Both countries were prospering economically - and China did not then seem a plausible challenger to America's position as the world's only superpower.

But it's also a day to honor the American worker - to reaffirm our commitment to the great American middle class that has, for generations, made our economy the envy of the world.