@Starrynight: NYT reporter Ron Susskind quoting a "high Bush admin official", thought widely to be Karl Rove, who said: "We're an empire now, and when we act, we create our own reality. And while you're studying that reality - judiciously, as you will - we'll act again, creating other new realities, which you can study too, and that's how things will sort out. We're history's actors... and you, all of you, will be left to just study what we do."

Certainly the impetus to global empire accelerated in the wake of WW2, which left the world in ruins, except for the undamaged USA. However, the imperial bug infected the USA as early as the late 19th century which was opposed by a number of American thinkers & writers including Mark Twain, brothers William and Henry James, Andrew Carnegie and former president Grover Cleveland.

You may be interested in the book "Imperial Cruise" by James Bradley, who incidentally was the son of one of the five who raise the flag over Iwo Jima