There is a familiar liberal lament that the United States had the sympathy of the world after September 11, but uselessly squandered it in the years that followed. The man who most vehemently espoused this line of thinking in France, former French President Jacques Chirac, is gone and consigned to oblivion. The French leader who replaced him, Nicolas Sarkozy, stood before a joint session of the U.S. Congress in November and offered a poetic tribute to the land his predecessor mocked. He recalled the young American soldiers buried long ago on French soil: “Fathers took their sons to the beaches where the young men of America so heroically died . . . The children of my generation understood that those young Americans, 20 years old, were true heroes to whom they owed the fact that they were free people and not slaves. France will never forget the sacrifice of your children.” The anti-Americanism that France gave voice to for a generation has given way to a new order. This young leader now wants to fashion France in America’s image.

The man or woman who picks up George W. Bush’s standard in 2009 will inherit an enviable legacy. Europe is at peace with U.S. leadership. India and China export the best of their younger generations to U.S. shores. Violent extremists are on the retreat. Millions have been lifted out of dire poverty. This age belongs to the Pax Americana, an era in which anti-Americanism has always been false and contrived, the pretense of intellectuals and pundits who shelter under American power while bemoaning the sins of the country that provides their protection. When and if a post-American world arrives, it will not be pretty or merciful. If we be Rome, darkness will follow the American imperium.

Nothing dramatically new needs to be done by the next...